Mixing
recursive func to find prime factors
0
i made a recursive function to find the prime factors of a number but it has a bug which makes turbo c quit. please help
#include<stdio.h>
#include<conio.h>
int prime(int num);
int primefactor(int num,int i);
void main(void)
{
int num;
printf("Enter a number whose prime factors are to be calculated:");
scanf("%d",&num);
primefactor(num,i);
i=num
getch();
}
int primefactor(int num,int i)
{
if(i==2)
return 1;
if(num%i==0)
{
if(prime(num))
{
printf(",%d",num);
num=num/i;
i++;
}
}
i--;
primefactor(num,i);
return 0;
}
int prime(int num)
{
int i,flag;
for(i=2;i<num;i++)
{
if(num%i==0)
flag=0;
}
return flag;
}
c recursion
edited Jan 18 '13 at 11:16
Ren
1,05941524
asked Jul 10 '10 at 22:59
Fahad UddinFahad Uddin
7,08653143233
|
show 2 more comments
0
i made a recursive function to find the prime factors of a number but it has a bug which makes turbo c quit. please help
#include<stdio.h>
#include<conio.h>
int prime(int num);
int primefactor(int num,int i);
void main(void)
{
int num;
printf("Enter a number whose prime factors are to be calculated:");
scanf("%d",&num);
primefactor(num,i);
i=num
getch();
}
int primefactor(int num,int i)
{
if(i==2)
return 1;
if(num%i==0)
{
if(prime(num))
{
printf(",%d",num);
num=num/i;
i++;
}
}
i--;
primefactor(num,i);
return 0;
}
int prime(int num)
{
int i,flag;
for(i=2;i<num;i++)
{
if(num%i==0)
flag=0;
}
return flag;
}
c recursion
edited Jan 18 '13 at 11:16
Ren
1,05941524
asked Jul 10 '10 at 22:59
Fahad UddinFahad Uddin
7,08653143233
7
Turbo C? As in, the 1980s-era C compiler?
– James McNellis
Jul 10 '10 at 23:02
On what line is the compiler reporting problems and/or crashing? You have given no information which might be useful for people to help resolve your problems.
– James McNellis
Jul 10 '10 at 23:03
1
borland turbo c 3 something ..i dont get why i am being taught it in the university :(
– Fahad Uddin
Jul 10 '10 at 23:10
You need to set flag = 1 inprime, and return it at the end. Or, better, when you find a factor, return 0; if you drop off the end of the loop, return 1. Note that you really only need to go as far as the square root of num to look for factors. This doesn't matter much when you've only fewer than 10 digits in the number, but it really does matter if you have many more digits.
– Jonathan Leffler
Jul 10 '10 at 23:41
1
@James: Turbo C was very much in action in academic world till at least 2003 :)
– neal aise
Jul 10 '10 at 23:58
|
show 2 more comments
0
0
0
i made a recursive function to find the prime factors of a number but it has a bug which makes turbo c quit. please help
#include<stdio.h>
#include<conio.h>
int prime(int num);
int primefactor(int num,int i);
void main(void)
{
int num;
printf("Enter a number whose prime factors are to be calculated:");
scanf("%d",&num);
primefactor(num,i);
i=num
getch();
}
int primefactor(int num,int i)
{
if(i==2)
return 1;
if(num%i==0)
{
if(prime(num))
{
printf(",%d",num);
num=num/i;
i++;
}
}
i--;
primefactor(num,i);
return 0;
}
int prime(int num)
{
int i,flag;
for(i=2;i<num;i++)
{
if(num%i==0)
flag=0;
}
return flag;
}
c recursion
edited Jan 18 '13 at 11:16
Ren
1,05941524
asked Jul 10 '10 at 22:59
Fahad UddinFahad Uddin
7,08653143233
i made a recursive function to find the prime factors of a number but it has a bug which makes turbo c quit. please help
#include<stdio.h>
#include<conio.h>
int prime(int num);
int primefactor(int num,int i);
void main(void)
{
int num;
printf("Enter a number whose prime factors are to be calculated:");
scanf("%d",&num);
primefactor(num,i);
i=num
getch();
}
int primefactor(int num,int i)
{
if(i==2)
return 1;
if(num%i==0)
{
if(prime(num))
{
printf(",%d",num);
num=num/i;
i++;
}
}
i--;
primefactor(num,i);
return 0;
}
int prime(int num)
{
int i,flag;
for(i=2;i<num;i++)
{
if(num%i==0)
flag=0;
}
return flag;
}
c recursion
c recursion
edited Jan 18 '13 at 11:16
Ren
1,05941524
asked Jul 10 '10 at 22:59
Fahad UddinFahad Uddin
7,08653143233
edited Jan 18 '13 at 11:16
Ren
1,05941524
asked Jul 10 '10 at 22:59
Fahad UddinFahad Uddin
7,08653143233
edited Jan 18 '13 at 11:16
Ren
1,05941524
edited Jan 18 '13 at 11:16
Ren
1,05941524
edited Jan 18 '13 at 11:16
Ren
1,05941524
1,05941524
asked Jul 10 '10 at 22:59
Fahad UddinFahad Uddin
7,08653143233
asked Jul 10 '10 at 22:59
Fahad UddinFahad Uddin
7,08653143233
asked Jul 10 '10 at 22:59
Fahad UddinFahad Uddin
7,08653143233
7,08653143233
7
Turbo C? As in, the 1980s-era C compiler?
– James McNellis
Jul 10 '10 at 23:02
On what line is the compiler reporting problems and/or crashing? You have given no information which might be useful for people to help resolve your problems.
– James McNellis
Jul 10 '10 at 23:03
1
borland turbo c 3 something ..i dont get why i am being taught it in the university :(
– Fahad Uddin
Jul 10 '10 at 23:10
You need to set flag = 1 inprime, and return it at the end. Or, better, when you find a factor, return 0; if you drop off the end of the loop, return 1. Note that you really only need to go as far as the square root of num to look for factors. This doesn't matter much when you've only fewer than 10 digits in the number, but it really does matter if you have many more digits.
– Jonathan Leffler
Jul 10 '10 at 23:41
1
@James: Turbo C was very much in action in academic world till at least 2003 :)
– neal aise
Jul 10 '10 at 23:58
|
show 2 more comments
7
Turbo C? As in, the 1980s-era C compiler?
– James McNellis
Jul 10 '10 at 23:02
On what line is the compiler reporting problems and/or crashing? You have given no information which might be useful for people to help resolve your problems.
– James McNellis
Jul 10 '10 at 23:03
1
borland turbo c 3 something ..i dont get why i am being taught it in the university :(
– Fahad Uddin
Jul 10 '10 at 23:10
You need to set flag = 1 inprime, and return it at the end. Or, better, when you find a factor, return 0; if you drop off the end of the loop, return 1. Note that you really only need to go as far as the square root of num to look for factors. This doesn't matter much when you've only fewer than 10 digits in the number, but it really does matter if you have many more digits.
– Jonathan Leffler
Jul 10 '10 at 23:41
1
@James: Turbo C was very much in action in academic world till at least 2003 :)
– neal aise
Jul 10 '10 at 23:58
7
7
Turbo C? As in, the 1980s-era C compiler?
– James McNellis
Jul 10 '10 at 23:02
Turbo C? As in, the 1980s-era C compiler?
– James McNellis
Jul 10 '10 at 23:02
On what line is the compiler reporting problems and/or crashing? You have given no information which might be useful for people to help resolve your problems.
– James McNellis
Jul 10 '10 at 23:03
On what line is the compiler reporting problems and/or crashing? You have given no information which might be useful for people to help resolve your problems.
– James McNellis
Jul 10 '10 at 23:03
1
1
borland turbo c 3 something ..i dont get why i am being taught it in the university :(
– Fahad Uddin
Jul 10 '10 at 23:10
borland turbo c 3 something ..i dont get why i am being taught it in the university :(
– Fahad Uddin
Jul 10 '10 at 23:10
You need to set flag = 1 in
prime, and return it at the end. Or, better, when you find a factor, return 0; if you drop off the end of the loop, return 1. Note that you really only need to go as far as the square root of num to look for factors. This doesn't matter much when you've only fewer than 10 digits in the number, but it really does matter if you have many more digits.– Jonathan Leffler
Jul 10 '10 at 23:41
You need to set flag = 1 in
prime, and return it at the end. Or, better, when you find a factor, return 0; if you drop off the end of the loop, return 1. Note that you really only need to go as far as the square root of num to look for factors. This doesn't matter much when you've only fewer than 10 digits in the number, but it really does matter if you have many more digits.– Jonathan Leffler
Jul 10 '10 at 23:41
1
1
@James: Turbo C was very much in action in academic world till at least 2003 :)
– neal aise
Jul 10 '10 at 23:58
@James: Turbo C was very much in action in academic world till at least 2003 :)
– neal aise
Jul 10 '10 at 23:58
|
show 2 more comments
10 Answers
10
active
oldest
votes
1
(little too sleepy to write good code.. so am sorry in advance for any bugs :p )
a simpler non recursive version
printPrimeFactors(int num) {
for (i = 2; i < sqrt(num); i=getNextPrime()) {
if (num %i)
printf("%d", i);
}
}
if you have to use recursion
printPrimeFactors(int num) {
if(isPrime(num)) {
printf ("%d ", num);
} else {
for(i=2; i < sqrt(num); i++) {
if(num%i ==0) {
printPrimeFactors(i);
printPrimeFactors(num/i);
}
}
}
}
answered Jul 10 '10 at 23:53
neal aiseneal aise
680412
Can any1 explain that :(
– Fahad Uddin
Jul 14 '10 at 12:48
will put in some explanation soon. sorry about that
– neal aise
Jul 15 '10 at 10:26
1
are you still sleepy? or you should have corrected this code by now
– SouvikMaji
Apr 18 '15 at 5:57
add a comment |
5
void main(void)
{
int num,i=num; // (*)
printf("Enter a number whose prime factors are to be calculated:");
scanf("%d",&num);
primefactor(num,i);
getch();
}
What value do you think i will have in (*)?
Not sure what you want i to start out as, but I'm pretty sure you don't want it to be something random. If you want it to start with the value of num, you need to assign num to it after you read it:
void main(void)
{
int num,i;
printf("Enter a number whose prime factors are to be calculated:");
scanf("%d",&num);
i = num; // assignment goes here.
primefactor(num,i);
getch();
}
answered Jul 10 '10 at 23:07
IVladIVlad
37.3k1187164
oh lol so stupid of me :P thanks a lot :)
– Fahad Uddin
Jul 10 '10 at 23:11
void main? =(
– jamesdlin
Jul 11 '10 at 0:24
i tried my best to get out of void main but this is what i am being taught :( int main() is many a times better
– Fahad Uddin
Jul 14 '10 at 12:45
@fahad it has to be int main(void) in your case (the other case is when you have command line params) educate your teachers with this: en.wikipedia.org/wiki/Main_function_(programming)#C_and_C.2B.2B
– neal aise
Jul 15 '10 at 10:25
add a comment |
1
Full recursive solution in c++ (for c replace cout lines with printf):
void printPrimeFactors(int num)
{
static int divisor = 2; // 2 is the first prime number
if ( num == 1 ) //if num = 1 we finished
{
divisor = 2; //restore divisor, so it'll be ready for the next run
return;
}
else if ( num % divisor == 0 ) //if num divided by divisor
{
cout << divisor << " "; //print divisor
printPrimeFactors( num / divisor ); //call the function with num/divisor
}
else //if num not divided by divisor
{
divisor++; //increase divisor
printPrimeFactors( num );
}
}
answered Jan 12 '13 at 17:05
yakiroyakiro
66848
Why is thestatica must in this case?
– shinzou
Dec 10 '14 at 19:48
add a comment |
1
The best way to implement prime factorization with low overhead function calls would be . . .
void factors(int number)
{
int divisor = 2;
if (number == 1) { cout << "1"; return; }
while ((number % divisor) && (number > divisor)) divisor++;
cout << divisor << ", ";
factors(number / divisor);
}
The number of function calls (recursion) is equal to the number of prime factors, including 1.
answered Oct 24 '13 at 16:28
IntrovertisIntrovertis
111
add a comment |
1
I did this in C. Depending on the compiler, minor changes might be needed to make in the program.
#include<stdio.h>
int primefact(int);
int main()
{
int n;
printf("Enter a number whose prime factors are to be calculated : n");
scanf_s("%d", &n);
printf("Prime factors of %d are : ");
primefact(n);
printf("n");
return 0;
}
int primefact(int n)
{
int i=2;
while(n%i!=0)
i++;
printf("%d ", i);
if(n==i)
return 0;
else
primefact(n/i);
}
edited Jun 23 '15 at 19:44
Ivan
2,56151952
answered Jun 23 '15 at 19:00
user5041802user5041802
111
add a comment |
0
Agree with IVlad - also, what happens in the case when num is prime? How many times will the recursive function be called for e.g. num = 7?
answered Jul 10 '10 at 23:09
Will AWill A
22.2k13857
...and - how does prime return it's value to the caller?
– Will A
Jul 10 '10 at 23:14
i used my concept of prime factor calculation and a prime factor program made without recursion for the help. pastebin.com/fVbjFGzQ
– Fahad Uddin
Jul 10 '10 at 23:19
I don't see a return statement anywhere in your prime function. Also - try going through the code with num = 7 (and the i = num assignment in the right place) and see what happens...
– Will A
Jul 10 '10 at 23:21
add a comment |
0
#include<stdio.h>
#include<stdlib.h>
int ar[10]={0};
int i=0,j=2;
void P(int n)
{
if(n<=1){
return ;
}
else{
if(n%j == 0){
printf("%dt",j);
n=n/j;
}
else{
j++;
}
P(n);
}
}
int main(void)
{
int n;
printf("Enter n = ");
scanf("%d",&n);
P(n);
printf("n");
return 0;
}
answered Jul 4 '14 at 17:48
PrashantPrashant
1
I suggest you don't include the corrected code, just an explanation of the error in question and the general direction on how to fix it.
– Theocharis K.
Jul 4 '14 at 18:10
There's no need to add an answer to an already properly answered question. And as @TheocharisK. said, please add also an explanation to your answer next time. And btw... Welcome to SO.
– Pr0gr4mm3r
Jul 4 '14 at 18:13
add a comment |
0
// recursivePrime.cpp
// Purpose: factor finding for an integer
// Author: Ping-Sung Liao, Kaohsiung,TAIWAN
// Date: 2017/02/02
// Version : 1.0
// Reference:
// http://stackoverflow.com/questions/3221156/recursive-func-to-find-prime-factors
#include<stdio.h>
#include<stdlib.h>
#include<math.h>
int primefactor(int num,int i);
int main(void)
{
int num, i;
printf("Enter a number whose prime factors are to be calculated:");
scanf("%d",&num);
i=int ( sqrt (num) );
primefactor(num,i);
system("pause"); // instead of getch()
}
int primefactor(int num,int i)
{ printf("num %d i=%dn", num, i);
if (i==1)
printf("prime found= %dn", num); // prime appearing in he variuable num
else if(num%i==0)
{ primefactor( int (num/i) , int ( sqrt(num/i) ) );
primefactor( i , int (sqrt ( i ) ) );
}
else
{ i--;
primefactor(num,i);
}
return 0;
}
answered Feb 2 '17 at 14:32
bsliaobsliao
11
1
While this code may answer the question, providing additional context regarding how and/or why it solves the problem would improve the answer's long-term value.
– Donald Duck
Feb 2 '17 at 14:43
add a comment |
0
#include <`stdio.h`>
void pf(int,int);
int main()
{
int a,i=2;
printf("Enter the Number:n");
scanf("%d",&a);
pf(a,i);
}
void pf(int x,int y)
{
if(x==1)
return 1;
else
{
if(x%y==0)
{printf("%dt",y);
pf(x/y,y);
}
else
{
y++;
pf(x,y);
}
}
}
edited Jan 1 at 12:26
Sumithran
8173822
answered Jan 1 at 5:47
Mayur AnklekarMayur Anklekar
1
add a comment |
-1
Implementation in java..
public class PrimeFactor {
public int divisor=2;
void printPrimeFactors(int num)
{
if(num == 1)
return;
if(num%divisor!=0)
{
while(num%divisor!=0)
++divisor;
}
if(num%divisor==0){
System.out.println(divisor);
printPrimeFactors(num/divisor);
}
}
public static void main(String args)
{
PrimeFactor obj = new PrimeFactor();
obj.printPrimeFactors(90);
}
}
answered May 11 '15 at 20:29
RajRaj
286310
Beyond attempting to solve the original question, this isn't relevant to the Turbo C issue raised in the original question.
– Sam Storie
May 11 '15 at 20:40
A quick explanation as to why this is the right way to do it would be beneficial.
– David
May 11 '15 at 20:53
add a comment |
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10 Answers
10
active
oldest
votes
10 Answers
10
active
oldest
votes
active
oldest
votes
active
oldest
votes
1
(little too sleepy to write good code.. so am sorry in advance for any bugs :p )
a simpler non recursive version
printPrimeFactors(int num) {
for (i = 2; i < sqrt(num); i=getNextPrime()) {
if (num %i)
printf("%d", i);
}
}
if you have to use recursion
printPrimeFactors(int num) {
if(isPrime(num)) {
printf ("%d ", num);
} else {
for(i=2; i < sqrt(num); i++) {
if(num%i ==0) {
printPrimeFactors(i);
printPrimeFactors(num/i);
}
}
}
}
answered Jul 10 '10 at 23:53
neal aiseneal aise
680412
Can any1 explain that :(
– Fahad Uddin
Jul 14 '10 at 12:48
will put in some explanation soon. sorry about that
– neal aise
Jul 15 '10 at 10:26
1
are you still sleepy? or you should have corrected this code by now
– SouvikMaji
Apr 18 '15 at 5:57
add a comment |
1
(little too sleepy to write good code.. so am sorry in advance for any bugs :p )
a simpler non recursive version
printPrimeFactors(int num) {
for (i = 2; i < sqrt(num); i=getNextPrime()) {
if (num %i)
printf("%d", i);
}
}
if you have to use recursion
printPrimeFactors(int num) {
if(isPrime(num)) {
printf ("%d ", num);
} else {
for(i=2; i < sqrt(num); i++) {
if(num%i ==0) {
printPrimeFactors(i);
printPrimeFactors(num/i);
}
}
}
}
answered Jul 10 '10 at 23:53
neal aiseneal aise
680412
Can any1 explain that :(
– Fahad Uddin
Jul 14 '10 at 12:48
will put in some explanation soon. sorry about that
– neal aise
Jul 15 '10 at 10:26
1
are you still sleepy? or you should have corrected this code by now
– SouvikMaji
Apr 18 '15 at 5:57
add a comment |
1
1
1
(little too sleepy to write good code.. so am sorry in advance for any bugs :p )
a simpler non recursive version
printPrimeFactors(int num) {
for (i = 2; i < sqrt(num); i=getNextPrime()) {
if (num %i)
printf("%d", i);
}
}
if you have to use recursion
printPrimeFactors(int num) {
if(isPrime(num)) {
printf ("%d ", num);
} else {
for(i=2; i < sqrt(num); i++) {
if(num%i ==0) {
printPrimeFactors(i);
printPrimeFactors(num/i);
}
}
}
}
answered Jul 10 '10 at 23:53
neal aiseneal aise
680412
(little too sleepy to write good code.. so am sorry in advance for any bugs :p )
a simpler non recursive version
printPrimeFactors(int num) {
for (i = 2; i < sqrt(num); i=getNextPrime()) {
if (num %i)
printf("%d", i);
}
}
if you have to use recursion
printPrimeFactors(int num) {
if(isPrime(num)) {
printf ("%d ", num);
} else {
for(i=2; i < sqrt(num); i++) {
if(num%i ==0) {
printPrimeFactors(i);
printPrimeFactors(num/i);
}
}
}
}
answered Jul 10 '10 at 23:53
neal aiseneal aise
680412
answered Jul 10 '10 at 23:53
neal aiseneal aise
680412
answered Jul 10 '10 at 23:53
neal aiseneal aise
680412
answered Jul 10 '10 at 23:53
neal aiseneal aise
680412
680412
Can any1 explain that :(
– Fahad Uddin
Jul 14 '10 at 12:48
will put in some explanation soon. sorry about that
– neal aise
Jul 15 '10 at 10:26
1
are you still sleepy? or you should have corrected this code by now
– SouvikMaji
Apr 18 '15 at 5:57
add a comment |
Can any1 explain that :(
– Fahad Uddin
Jul 14 '10 at 12:48
will put in some explanation soon. sorry about that
– neal aise
Jul 15 '10 at 10:26
1
are you still sleepy? or you should have corrected this code by now
– SouvikMaji
Apr 18 '15 at 5:57
Can any1 explain that :(
– Fahad Uddin
Jul 14 '10 at 12:48
Can any1 explain that :(
– Fahad Uddin
Jul 14 '10 at 12:48
will put in some explanation soon. sorry about that
– neal aise
Jul 15 '10 at 10:26
will put in some explanation soon. sorry about that
– neal aise
Jul 15 '10 at 10:26
1
1
are you still sleepy? or you should have corrected this code by now
– SouvikMaji
Apr 18 '15 at 5:57
are you still sleepy? or you should have corrected this code by now
– SouvikMaji
Apr 18 '15 at 5:57
add a comment |
5
void main(void)
{
int num,i=num; // (*)
printf("Enter a number whose prime factors are to be calculated:");
scanf("%d",&num);
primefactor(num,i);
getch();
}
What value do you think i will have in (*)?
Not sure what you want i to start out as, but I'm pretty sure you don't want it to be something random. If you want it to start with the value of num, you need to assign num to it after you read it:
void main(void)
{
int num,i;
printf("Enter a number whose prime factors are to be calculated:");
scanf("%d",&num);
i = num; // assignment goes here.
primefactor(num,i);
getch();
}
answered Jul 10 '10 at 23:07
IVladIVlad
37.3k1187164
oh lol so stupid of me :P thanks a lot :)
– Fahad Uddin
Jul 10 '10 at 23:11
void main? =(
– jamesdlin
Jul 11 '10 at 0:24
i tried my best to get out of void main but this is what i am being taught :( int main() is many a times better
– Fahad Uddin
Jul 14 '10 at 12:45
@fahad it has to be int main(void) in your case (the other case is when you have command line params) educate your teachers with this: en.wikipedia.org/wiki/Main_function_(programming)#C_and_C.2B.2B
– neal aise
Jul 15 '10 at 10:25
add a comment |
5
void main(void)
{
int num,i=num; // (*)
printf("Enter a number whose prime factors are to be calculated:");
scanf("%d",&num);
primefactor(num,i);
getch();
}
What value do you think i will have in (*)?
Not sure what you want i to start out as, but I'm pretty sure you don't want it to be something random. If you want it to start with the value of num, you need to assign num to it after you read it:
void main(void)
{
int num,i;
printf("Enter a number whose prime factors are to be calculated:");
scanf("%d",&num);
i = num; // assignment goes here.
primefactor(num,i);
getch();
}
answered Jul 10 '10 at 23:07
IVladIVlad
37.3k1187164
oh lol so stupid of me :P thanks a lot :)
– Fahad Uddin
Jul 10 '10 at 23:11
void main? =(
– jamesdlin
Jul 11 '10 at 0:24
i tried my best to get out of void main but this is what i am being taught :( int main() is many a times better
– Fahad Uddin
Jul 14 '10 at 12:45
@fahad it has to be int main(void) in your case (the other case is when you have command line params) educate your teachers with this: en.wikipedia.org/wiki/Main_function_(programming)#C_and_C.2B.2B
– neal aise
Jul 15 '10 at 10:25
add a comment |
5
5
5
void main(void)
{
int num,i=num; // (*)
printf("Enter a number whose prime factors are to be calculated:");
scanf("%d",&num);
primefactor(num,i);
getch();
}
What value do you think i will have in (*)?
Not sure what you want i to start out as, but I'm pretty sure you don't want it to be something random. If you want it to start with the value of num, you need to assign num to it after you read it:
void main(void)
{
int num,i;
printf("Enter a number whose prime factors are to be calculated:");
scanf("%d",&num);
i = num; // assignment goes here.
primefactor(num,i);
getch();
}
answered Jul 10 '10 at 23:07
IVladIVlad
37.3k1187164
void main(void)
{
int num,i=num; // (*)
printf("Enter a number whose prime factors are to be calculated:");
scanf("%d",&num);
primefactor(num,i);
getch();
}
What value do you think i will have in (*)?
Not sure what you want i to start out as, but I'm pretty sure you don't want it to be something random. If you want it to start with the value of num, you need to assign num to it after you read it:
void main(void)
{
int num,i;
printf("Enter a number whose prime factors are to be calculated:");
scanf("%d",&num);
i = num; // assignment goes here.
primefactor(num,i);
getch();
}
answered Jul 10 '10 at 23:07
IVladIVlad
37.3k1187164
answered Jul 10 '10 at 23:07
IVladIVlad
37.3k1187164
answered Jul 10 '10 at 23:07
IVladIVlad
37.3k1187164
answered Jul 10 '10 at 23:07
IVladIVlad
37.3k1187164
37.3k1187164
oh lol so stupid of me :P thanks a lot :)
– Fahad Uddin
Jul 10 '10 at 23:11
void main? =(
– jamesdlin
Jul 11 '10 at 0:24
i tried my best to get out of void main but this is what i am being taught :( int main() is many a times better
– Fahad Uddin
Jul 14 '10 at 12:45
@fahad it has to be int main(void) in your case (the other case is when you have command line params) educate your teachers with this: en.wikipedia.org/wiki/Main_function_(programming)#C_and_C.2B.2B
– neal aise
Jul 15 '10 at 10:25
add a comment |
oh lol so stupid of me :P thanks a lot :)
– Fahad Uddin
Jul 10 '10 at 23:11
void main? =(
– jamesdlin
Jul 11 '10 at 0:24
i tried my best to get out of void main but this is what i am being taught :( int main() is many a times better
– Fahad Uddin
Jul 14 '10 at 12:45
@fahad it has to be int main(void) in your case (the other case is when you have command line params) educate your teachers with this: en.wikipedia.org/wiki/Main_function_(programming)#C_and_C.2B.2B
– neal aise
Jul 15 '10 at 10:25
oh lol so stupid of me :P thanks a lot :)
– Fahad Uddin
Jul 10 '10 at 23:11
oh lol so stupid of me :P thanks a lot :)
– Fahad Uddin
Jul 10 '10 at 23:11
void main? =(– jamesdlin
Jul 11 '10 at 0:24
void main? =(– jamesdlin
Jul 11 '10 at 0:24
i tried my best to get out of void main but this is what i am being taught :( int main() is many a times better
– Fahad Uddin
Jul 14 '10 at 12:45
i tried my best to get out of void main but this is what i am being taught :( int main() is many a times better
– Fahad Uddin
Jul 14 '10 at 12:45
@fahad it has to be int main(void) in your case (the other case is when you have command line params) educate your teachers with this: en.wikipedia.org/wiki/Main_function_(programming)#C_and_C.2B.2B
– neal aise
Jul 15 '10 at 10:25
@fahad it has to be int main(void) in your case (the other case is when you have command line params) educate your teachers with this: en.wikipedia.org/wiki/Main_function_(programming)#C_and_C.2B.2B
– neal aise
Jul 15 '10 at 10:25
add a comment |
1
Full recursive solution in c++ (for c replace cout lines with printf):
void printPrimeFactors(int num)
{
static int divisor = 2; // 2 is the first prime number
if ( num == 1 ) //if num = 1 we finished
{
divisor = 2; //restore divisor, so it'll be ready for the next run
return;
}
else if ( num % divisor == 0 ) //if num divided by divisor
{
cout << divisor << " "; //print divisor
printPrimeFactors( num / divisor ); //call the function with num/divisor
}
else //if num not divided by divisor
{
divisor++; //increase divisor
printPrimeFactors( num );
}
}
answered Jan 12 '13 at 17:05
yakiroyakiro
66848
Why is thestatica must in this case?
– shinzou
Dec 10 '14 at 19:48
add a comment |
1
Full recursive solution in c++ (for c replace cout lines with printf):
void printPrimeFactors(int num)
{
static int divisor = 2; // 2 is the first prime number
if ( num == 1 ) //if num = 1 we finished
{
divisor = 2; //restore divisor, so it'll be ready for the next run
return;
}
else if ( num % divisor == 0 ) //if num divided by divisor
{
cout << divisor << " "; //print divisor
printPrimeFactors( num / divisor ); //call the function with num/divisor
}
else //if num not divided by divisor
{
divisor++; //increase divisor
printPrimeFactors( num );
}
}
answered Jan 12 '13 at 17:05
yakiroyakiro
66848
Why is thestatica must in this case?
– shinzou
Dec 10 '14 at 19:48
add a comment |
1
1
1
Full recursive solution in c++ (for c replace cout lines with printf):
void printPrimeFactors(int num)
{
static int divisor = 2; // 2 is the first prime number
if ( num == 1 ) //if num = 1 we finished
{
divisor = 2; //restore divisor, so it'll be ready for the next run
return;
}
else if ( num % divisor == 0 ) //if num divided by divisor
{
cout << divisor << " "; //print divisor
printPrimeFactors( num / divisor ); //call the function with num/divisor
}
else //if num not divided by divisor
{
divisor++; //increase divisor
printPrimeFactors( num );
}
}
answered Jan 12 '13 at 17:05
yakiroyakiro
66848
Full recursive solution in c++ (for c replace cout lines with printf):
void printPrimeFactors(int num)
{
static int divisor = 2; // 2 is the first prime number
if ( num == 1 ) //if num = 1 we finished
{
divisor = 2; //restore divisor, so it'll be ready for the next run
return;
}
else if ( num % divisor == 0 ) //if num divided by divisor
{
cout << divisor << " "; //print divisor
printPrimeFactors( num / divisor ); //call the function with num/divisor
}
else //if num not divided by divisor
{
divisor++; //increase divisor
printPrimeFactors( num );
}
}
answered Jan 12 '13 at 17:05
yakiroyakiro
66848
answered Jan 12 '13 at 17:05
yakiroyakiro
66848
answered Jan 12 '13 at 17:05
yakiroyakiro
66848
answered Jan 12 '13 at 17:05
yakiroyakiro
66848
66848
Why is thestatica must in this case?
– shinzou
Dec 10 '14 at 19:48
add a comment |
Why is thestatica must in this case?
– shinzou
Dec 10 '14 at 19:48
Why is the
static a must in this case?– shinzou
Dec 10 '14 at 19:48
Why is the
static a must in this case?– shinzou
Dec 10 '14 at 19:48
add a comment |
1
The best way to implement prime factorization with low overhead function calls would be . . .
void factors(int number)
{
int divisor = 2;
if (number == 1) { cout << "1"; return; }
while ((number % divisor) && (number > divisor)) divisor++;
cout << divisor << ", ";
factors(number / divisor);
}
The number of function calls (recursion) is equal to the number of prime factors, including 1.
answered Oct 24 '13 at 16:28
IntrovertisIntrovertis
111
add a comment |
1
The best way to implement prime factorization with low overhead function calls would be . . .
void factors(int number)
{
int divisor = 2;
if (number == 1) { cout << "1"; return; }
while ((number % divisor) && (number > divisor)) divisor++;
cout << divisor << ", ";
factors(number / divisor);
}
The number of function calls (recursion) is equal to the number of prime factors, including 1.
answered Oct 24 '13 at 16:28
IntrovertisIntrovertis
111
add a comment |
1
1
1
The best way to implement prime factorization with low overhead function calls would be . . .
void factors(int number)
{
int divisor = 2;
if (number == 1) { cout << "1"; return; }
while ((number % divisor) && (number > divisor)) divisor++;
cout << divisor << ", ";
factors(number / divisor);
}
The number of function calls (recursion) is equal to the number of prime factors, including 1.
answered Oct 24 '13 at 16:28
IntrovertisIntrovertis
111
The best way to implement prime factorization with low overhead function calls would be . . .
void factors(int number)
{
int divisor = 2;
if (number == 1) { cout << "1"; return; }
while ((number % divisor) && (number > divisor)) divisor++;
cout << divisor << ", ";
factors(number / divisor);
}
The number of function calls (recursion) is equal to the number of prime factors, including 1.
answered Oct 24 '13 at 16:28
IntrovertisIntrovertis
111
answered Oct 24 '13 at 16:28
IntrovertisIntrovertis
111
answered Oct 24 '13 at 16:28
IntrovertisIntrovertis
111
answered Oct 24 '13 at 16:28
IntrovertisIntrovertis
111
111
add a comment |
add a comment |
1
I did this in C. Depending on the compiler, minor changes might be needed to make in the program.
#include<stdio.h>
int primefact(int);
int main()
{
int n;
printf("Enter a number whose prime factors are to be calculated : n");
scanf_s("%d", &n);
printf("Prime factors of %d are : ");
primefact(n);
printf("n");
return 0;
}
int primefact(int n)
{
int i=2;
while(n%i!=0)
i++;
printf("%d ", i);
if(n==i)
return 0;
else
primefact(n/i);
}
edited Jun 23 '15 at 19:44
Ivan
2,56151952
answered Jun 23 '15 at 19:00
user5041802user5041802
111
add a comment |
1
I did this in C. Depending on the compiler, minor changes might be needed to make in the program.
#include<stdio.h>
int primefact(int);
int main()
{
int n;
printf("Enter a number whose prime factors are to be calculated : n");
scanf_s("%d", &n);
printf("Prime factors of %d are : ");
primefact(n);
printf("n");
return 0;
}
int primefact(int n)
{
int i=2;
while(n%i!=0)
i++;
printf("%d ", i);
if(n==i)
return 0;
else
primefact(n/i);
}
edited Jun 23 '15 at 19:44
Ivan
2,56151952
answered Jun 23 '15 at 19:00
user5041802user5041802
111
add a comment |
1
1
1
I did this in C. Depending on the compiler, minor changes might be needed to make in the program.
#include<stdio.h>
int primefact(int);
int main()
{
int n;
printf("Enter a number whose prime factors are to be calculated : n");
scanf_s("%d", &n);
printf("Prime factors of %d are : ");
primefact(n);
printf("n");
return 0;
}
int primefact(int n)
{
int i=2;
while(n%i!=0)
i++;
printf("%d ", i);
if(n==i)
return 0;
else
primefact(n/i);
}
edited Jun 23 '15 at 19:44
Ivan
2,56151952
answered Jun 23 '15 at 19:00
user5041802user5041802
111
I did this in C. Depending on the compiler, minor changes might be needed to make in the program.
#include<stdio.h>
int primefact(int);
int main()
{
int n;
printf("Enter a number whose prime factors are to be calculated : n");
scanf_s("%d", &n);
printf("Prime factors of %d are : ");
primefact(n);
printf("n");
return 0;
}
int primefact(int n)
{
int i=2;
while(n%i!=0)
i++;
printf("%d ", i);
if(n==i)
return 0;
else
primefact(n/i);
}
edited Jun 23 '15 at 19:44
Ivan
2,56151952
answered Jun 23 '15 at 19:00
user5041802user5041802
111
edited Jun 23 '15 at 19:44
Ivan
2,56151952
edited Jun 23 '15 at 19:44
Ivan
2,56151952
edited Jun 23 '15 at 19:44
Ivan
2,56151952
2,56151952
answered Jun 23 '15 at 19:00
user5041802user5041802
111
answered Jun 23 '15 at 19:00
user5041802user5041802
111
answered Jun 23 '15 at 19:00
user5041802user5041802
111
111
add a comment |
add a comment |
0
Agree with IVlad - also, what happens in the case when num is prime? How many times will the recursive function be called for e.g. num = 7?
answered Jul 10 '10 at 23:09
Will AWill A
22.2k13857
...and - how does prime return it's value to the caller?
– Will A
Jul 10 '10 at 23:14
i used my concept of prime factor calculation and a prime factor program made without recursion for the help. pastebin.com/fVbjFGzQ
– Fahad Uddin
Jul 10 '10 at 23:19
I don't see a return statement anywhere in your prime function. Also - try going through the code with num = 7 (and the i = num assignment in the right place) and see what happens...
– Will A
Jul 10 '10 at 23:21
add a comment |
0
Agree with IVlad - also, what happens in the case when num is prime? How many times will the recursive function be called for e.g. num = 7?
answered Jul 10 '10 at 23:09
Will AWill A
22.2k13857
...and - how does prime return it's value to the caller?
– Will A
Jul 10 '10 at 23:14
i used my concept of prime factor calculation and a prime factor program made without recursion for the help. pastebin.com/fVbjFGzQ
– Fahad Uddin
Jul 10 '10 at 23:19
I don't see a return statement anywhere in your prime function. Also - try going through the code with num = 7 (and the i = num assignment in the right place) and see what happens...
– Will A
Jul 10 '10 at 23:21
add a comment |
0
0
0
Agree with IVlad - also, what happens in the case when num is prime? How many times will the recursive function be called for e.g. num = 7?
answered Jul 10 '10 at 23:09
Will AWill A
22.2k13857
Agree with IVlad - also, what happens in the case when num is prime? How many times will the recursive function be called for e.g. num = 7?
answered Jul 10 '10 at 23:09
Will AWill A
22.2k13857
answered Jul 10 '10 at 23:09
Will AWill A
22.2k13857
answered Jul 10 '10 at 23:09
Will AWill A
22.2k13857
answered Jul 10 '10 at 23:09
Will AWill A
22.2k13857
22.2k13857
...and - how does prime return it's value to the caller?
– Will A
Jul 10 '10 at 23:14
i used my concept of prime factor calculation and a prime factor program made without recursion for the help. pastebin.com/fVbjFGzQ
– Fahad Uddin
Jul 10 '10 at 23:19
I don't see a return statement anywhere in your prime function. Also - try going through the code with num = 7 (and the i = num assignment in the right place) and see what happens...
– Will A
Jul 10 '10 at 23:21
add a comment |
...and - how does prime return it's value to the caller?
– Will A
Jul 10 '10 at 23:14
i used my concept of prime factor calculation and a prime factor program made without recursion for the help. pastebin.com/fVbjFGzQ
– Fahad Uddin
Jul 10 '10 at 23:19
I don't see a return statement anywhere in your prime function. Also - try going through the code with num = 7 (and the i = num assignment in the right place) and see what happens...
– Will A
Jul 10 '10 at 23:21
...and - how does prime return it's value to the caller?
– Will A
Jul 10 '10 at 23:14
...and - how does prime return it's value to the caller?
– Will A
Jul 10 '10 at 23:14
i used my concept of prime factor calculation and a prime factor program made without recursion for the help. pastebin.com/fVbjFGzQ
– Fahad Uddin
Jul 10 '10 at 23:19
i used my concept of prime factor calculation and a prime factor program made without recursion for the help. pastebin.com/fVbjFGzQ
– Fahad Uddin
Jul 10 '10 at 23:19
I don't see a return statement anywhere in your prime function. Also - try going through the code with num = 7 (and the i = num assignment in the right place) and see what happens...
– Will A
Jul 10 '10 at 23:21
I don't see a return statement anywhere in your prime function. Also - try going through the code with num = 7 (and the i = num assignment in the right place) and see what happens...
– Will A
Jul 10 '10 at 23:21
add a comment |
0
#include<stdio.h>
#include<stdlib.h>
int ar[10]={0};
int i=0,j=2;
void P(int n)
{
if(n<=1){
return ;
}
else{
if(n%j == 0){
printf("%dt",j);
n=n/j;
}
else{
j++;
}
P(n);
}
}
int main(void)
{
int n;
printf("Enter n = ");
scanf("%d",&n);
P(n);
printf("n");
return 0;
}
answered Jul 4 '14 at 17:48
PrashantPrashant
1
I suggest you don't include the corrected code, just an explanation of the error in question and the general direction on how to fix it.
– Theocharis K.
Jul 4 '14 at 18:10
There's no need to add an answer to an already properly answered question. And as @TheocharisK. said, please add also an explanation to your answer next time. And btw... Welcome to SO.
– Pr0gr4mm3r
Jul 4 '14 at 18:13
add a comment |
0
#include<stdio.h>
#include<stdlib.h>
int ar[10]={0};
int i=0,j=2;
void P(int n)
{
if(n<=1){
return ;
}
else{
if(n%j == 0){
printf("%dt",j);
n=n/j;
}
else{
j++;
}
P(n);
}
}
int main(void)
{
int n;
printf("Enter n = ");
scanf("%d",&n);
P(n);
printf("n");
return 0;
}
answered Jul 4 '14 at 17:48
PrashantPrashant
1
I suggest you don't include the corrected code, just an explanation of the error in question and the general direction on how to fix it.
– Theocharis K.
Jul 4 '14 at 18:10
There's no need to add an answer to an already properly answered question. And as @TheocharisK. said, please add also an explanation to your answer next time. And btw... Welcome to SO.
– Pr0gr4mm3r
Jul 4 '14 at 18:13
add a comment |
0
0
0
#include<stdio.h>
#include<stdlib.h>
int ar[10]={0};
int i=0,j=2;
void P(int n)
{
if(n<=1){
return ;
}
else{
if(n%j == 0){
printf("%dt",j);
n=n/j;
}
else{
j++;
}
P(n);
}
}
int main(void)
{
int n;
printf("Enter n = ");
scanf("%d",&n);
P(n);
printf("n");
return 0;
}
answered Jul 4 '14 at 17:48
PrashantPrashant
1
#include<stdio.h>
#include<stdlib.h>
int ar[10]={0};
int i=0,j=2;
void P(int n)
{
if(n<=1){
return ;
}
else{
if(n%j == 0){
printf("%dt",j);
n=n/j;
}
else{
j++;
}
P(n);
}
}
int main(void)
{
int n;
printf("Enter n = ");
scanf("%d",&n);
P(n);
printf("n");
return 0;
}
answered Jul 4 '14 at 17:48
PrashantPrashant
1
answered Jul 4 '14 at 17:48
PrashantPrashant
1
answered Jul 4 '14 at 17:48
PrashantPrashant
1
answered Jul 4 '14 at 17:48
PrashantPrashant
1
1
I suggest you don't include the corrected code, just an explanation of the error in question and the general direction on how to fix it.
– Theocharis K.
Jul 4 '14 at 18:10
There's no need to add an answer to an already properly answered question. And as @TheocharisK. said, please add also an explanation to your answer next time. And btw... Welcome to SO.
– Pr0gr4mm3r
Jul 4 '14 at 18:13
add a comment |
I suggest you don't include the corrected code, just an explanation of the error in question and the general direction on how to fix it.
– Theocharis K.
Jul 4 '14 at 18:10
There's no need to add an answer to an already properly answered question. And as @TheocharisK. said, please add also an explanation to your answer next time. And btw... Welcome to SO.
– Pr0gr4mm3r
Jul 4 '14 at 18:13
I suggest you don't include the corrected code, just an explanation of the error in question and the general direction on how to fix it.
– Theocharis K.
Jul 4 '14 at 18:10
I suggest you don't include the corrected code, just an explanation of the error in question and the general direction on how to fix it.
– Theocharis K.
Jul 4 '14 at 18:10
There's no need to add an answer to an already properly answered question. And as @TheocharisK. said, please add also an explanation to your answer next time. And btw... Welcome to SO.
– Pr0gr4mm3r
Jul 4 '14 at 18:13
There's no need to add an answer to an already properly answered question. And as @TheocharisK. said, please add also an explanation to your answer next time. And btw... Welcome to SO.
– Pr0gr4mm3r
Jul 4 '14 at 18:13
add a comment |
0
// recursivePrime.cpp
// Purpose: factor finding for an integer
// Author: Ping-Sung Liao, Kaohsiung,TAIWAN
// Date: 2017/02/02
// Version : 1.0
// Reference:
// http://stackoverflow.com/questions/3221156/recursive-func-to-find-prime-factors
#include<stdio.h>
#include<stdlib.h>
#include<math.h>
int primefactor(int num,int i);
int main(void)
{
int num, i;
printf("Enter a number whose prime factors are to be calculated:");
scanf("%d",&num);
i=int ( sqrt (num) );
primefactor(num,i);
system("pause"); // instead of getch()
}
int primefactor(int num,int i)
{ printf("num %d i=%dn", num, i);
if (i==1)
printf("prime found= %dn", num); // prime appearing in he variuable num
else if(num%i==0)
{ primefactor( int (num/i) , int ( sqrt(num/i) ) );
primefactor( i , int (sqrt ( i ) ) );
}
else
{ i--;
primefactor(num,i);
}
return 0;
}
answered Feb 2 '17 at 14:32
bsliaobsliao
11
1
While this code may answer the question, providing additional context regarding how and/or why it solves the problem would improve the answer's long-term value.
– Donald Duck
Feb 2 '17 at 14:43
add a comment |
0
// recursivePrime.cpp
// Purpose: factor finding for an integer
// Author: Ping-Sung Liao, Kaohsiung,TAIWAN
// Date: 2017/02/02
// Version : 1.0
// Reference:
// http://stackoverflow.com/questions/3221156/recursive-func-to-find-prime-factors
#include<stdio.h>
#include<stdlib.h>
#include<math.h>
int primefactor(int num,int i);
int main(void)
{
int num, i;
printf("Enter a number whose prime factors are to be calculated:");
scanf("%d",&num);
i=int ( sqrt (num) );
primefactor(num,i);
system("pause"); // instead of getch()
}
int primefactor(int num,int i)
{ printf("num %d i=%dn", num, i);
if (i==1)
printf("prime found= %dn", num); // prime appearing in he variuable num
else if(num%i==0)
{ primefactor( int (num/i) , int ( sqrt(num/i) ) );
primefactor( i , int (sqrt ( i ) ) );
}
else
{ i--;
primefactor(num,i);
}
return 0;
}
answered Feb 2 '17 at 14:32
bsliaobsliao
11
1
While this code may answer the question, providing additional context regarding how and/or why it solves the problem would improve the answer's long-term value.
– Donald Duck
Feb 2 '17 at 14:43
add a comment |
0
0
0
// recursivePrime.cpp
// Purpose: factor finding for an integer
// Author: Ping-Sung Liao, Kaohsiung,TAIWAN
// Date: 2017/02/02
// Version : 1.0
// Reference:
// http://stackoverflow.com/questions/3221156/recursive-func-to-find-prime-factors
#include<stdio.h>
#include<stdlib.h>
#include<math.h>
int primefactor(int num,int i);
int main(void)
{
int num, i;
printf("Enter a number whose prime factors are to be calculated:");
scanf("%d",&num);
i=int ( sqrt (num) );
primefactor(num,i);
system("pause"); // instead of getch()
}
int primefactor(int num,int i)
{ printf("num %d i=%dn", num, i);
if (i==1)
printf("prime found= %dn", num); // prime appearing in he variuable num
else if(num%i==0)
{ primefactor( int (num/i) , int ( sqrt(num/i) ) );
primefactor( i , int (sqrt ( i ) ) );
}
else
{ i--;
primefactor(num,i);
}
return 0;
}
answered Feb 2 '17 at 14:32
bsliaobsliao
11
// recursivePrime.cpp
// Purpose: factor finding for an integer
// Author: Ping-Sung Liao, Kaohsiung,TAIWAN
// Date: 2017/02/02
// Version : 1.0
// Reference:
// http://stackoverflow.com/questions/3221156/recursive-func-to-find-prime-factors
#include<stdio.h>
#include<stdlib.h>
#include<math.h>
int primefactor(int num,int i);
int main(void)
{
int num, i;
printf("Enter a number whose prime factors are to be calculated:");
scanf("%d",&num);
i=int ( sqrt (num) );
primefactor(num,i);
system("pause"); // instead of getch()
}
int primefactor(int num,int i)
{ printf("num %d i=%dn", num, i);
if (i==1)
printf("prime found= %dn", num); // prime appearing in he variuable num
else if(num%i==0)
{ primefactor( int (num/i) , int ( sqrt(num/i) ) );
primefactor( i , int (sqrt ( i ) ) );
}
else
{ i--;
primefactor(num,i);
}
return 0;
}
answered Feb 2 '17 at 14:32
bsliaobsliao
11
edited Feb 2 '17 at 14:59
answered Feb 2 '17 at 14:32
bsliaobsliao
11
answered Feb 2 '17 at 14:32
bsliaobsliao
11
answered Feb 2 '17 at 14:32
bsliaobsliao
11
11
1
While this code may answer the question, providing additional context regarding how and/or why it solves the problem would improve the answer's long-term value.
– Donald Duck
Feb 2 '17 at 14:43
add a comment |
1
While this code may answer the question, providing additional context regarding how and/or why it solves the problem would improve the answer's long-term value.
– Donald Duck
Feb 2 '17 at 14:43
1
1
While this code may answer the question, providing additional context regarding how and/or why it solves the problem would improve the answer's long-term value.
– Donald Duck
Feb 2 '17 at 14:43
While this code may answer the question, providing additional context regarding how and/or why it solves the problem would improve the answer's long-term value.
– Donald Duck
Feb 2 '17 at 14:43
add a comment |
0
#include <`stdio.h`>
void pf(int,int);
int main()
{
int a,i=2;
printf("Enter the Number:n");
scanf("%d",&a);
pf(a,i);
}
void pf(int x,int y)
{
if(x==1)
return 1;
else
{
if(x%y==0)
{printf("%dt",y);
pf(x/y,y);
}
else
{
y++;
pf(x,y);
}
}
}
edited Jan 1 at 12:26
Sumithran
8173822
answered Jan 1 at 5:47
Mayur AnklekarMayur Anklekar
1
add a comment |
0
#include <`stdio.h`>
void pf(int,int);
int main()
{
int a,i=2;
printf("Enter the Number:n");
scanf("%d",&a);
pf(a,i);
}
void pf(int x,int y)
{
if(x==1)
return 1;
else
{
if(x%y==0)
{printf("%dt",y);
pf(x/y,y);
}
else
{
y++;
pf(x,y);
}
}
}
edited Jan 1 at 12:26
Sumithran
8173822
answered Jan 1 at 5:47
Mayur AnklekarMayur Anklekar
1
add a comment |
0
0
0
#include <`stdio.h`>
void pf(int,int);
int main()
{
int a,i=2;
printf("Enter the Number:n");
scanf("%d",&a);
pf(a,i);
}
void pf(int x,int y)
{
if(x==1)
return 1;
else
{
if(x%y==0)
{printf("%dt",y);
pf(x/y,y);
}
else
{
y++;
pf(x,y);
}
}
}
edited Jan 1 at 12:26
Sumithran
8173822
answered Jan 1 at 5:47
Mayur AnklekarMayur Anklekar
1
#include <`stdio.h`>
void pf(int,int);
int main()
{
int a,i=2;
printf("Enter the Number:n");
scanf("%d",&a);
pf(a,i);
}
void pf(int x,int y)
{
if(x==1)
return 1;
else
{
if(x%y==0)
{printf("%dt",y);
pf(x/y,y);
}
else
{
y++;
pf(x,y);
}
}
}
edited Jan 1 at 12:26
Sumithran
8173822
answered Jan 1 at 5:47
Mayur AnklekarMayur Anklekar
1
edited Jan 1 at 12:26
Sumithran
8173822
edited Jan 1 at 12:26
Sumithran
8173822
edited Jan 1 at 12:26
Sumithran
8173822
8173822
answered Jan 1 at 5:47
Mayur AnklekarMayur Anklekar
1
answered Jan 1 at 5:47
Mayur AnklekarMayur Anklekar
1
answered Jan 1 at 5:47
Mayur AnklekarMayur Anklekar
1
1
add a comment |
add a comment |
-1
Implementation in java..
public class PrimeFactor {
public int divisor=2;
void printPrimeFactors(int num)
{
if(num == 1)
return;
if(num%divisor!=0)
{
while(num%divisor!=0)
++divisor;
}
if(num%divisor==0){
System.out.println(divisor);
printPrimeFactors(num/divisor);
}
}
public static void main(String args)
{
PrimeFactor obj = new PrimeFactor();
obj.printPrimeFactors(90);
}
}
answered May 11 '15 at 20:29
RajRaj
286310
Beyond attempting to solve the original question, this isn't relevant to the Turbo C issue raised in the original question.
– Sam Storie
May 11 '15 at 20:40
A quick explanation as to why this is the right way to do it would be beneficial.
– David
May 11 '15 at 20:53
add a comment |
-1
Implementation in java..
public class PrimeFactor {
public int divisor=2;
void printPrimeFactors(int num)
{
if(num == 1)
return;
if(num%divisor!=0)
{
while(num%divisor!=0)
++divisor;
}
if(num%divisor==0){
System.out.println(divisor);
printPrimeFactors(num/divisor);
}
}
public static void main(String args)
{
PrimeFactor obj = new PrimeFactor();
obj.printPrimeFactors(90);
}
}
answered May 11 '15 at 20:29
RajRaj
286310
Beyond attempting to solve the original question, this isn't relevant to the Turbo C issue raised in the original question.
– Sam Storie
May 11 '15 at 20:40
A quick explanation as to why this is the right way to do it would be beneficial.
– David
May 11 '15 at 20:53
add a comment |
-1
-1
-1
Implementation in java..
public class PrimeFactor {
public int divisor=2;
void printPrimeFactors(int num)
{
if(num == 1)
return;
if(num%divisor!=0)
{
while(num%divisor!=0)
++divisor;
}
if(num%divisor==0){
System.out.println(divisor);
printPrimeFactors(num/divisor);
}
}
public static void main(String args)
{
PrimeFactor obj = new PrimeFactor();
obj.printPrimeFactors(90);
}
}
answered May 11 '15 at 20:29
RajRaj
286310
Implementation in java..
public class PrimeFactor {
public int divisor=2;
void printPrimeFactors(int num)
{
if(num == 1)
return;
if(num%divisor!=0)
{
while(num%divisor!=0)
++divisor;
}
if(num%divisor==0){
System.out.println(divisor);
printPrimeFactors(num/divisor);
}
}
public static void main(String args)
{
PrimeFactor obj = new PrimeFactor();
obj.printPrimeFactors(90);
}
}
answered May 11 '15 at 20:29
RajRaj
286310
answered May 11 '15 at 20:29
RajRaj
286310
answered May 11 '15 at 20:29
RajRaj
286310
answered May 11 '15 at 20:29
RajRaj
286310
286310
Beyond attempting to solve the original question, this isn't relevant to the Turbo C issue raised in the original question.
– Sam Storie
May 11 '15 at 20:40
A quick explanation as to why this is the right way to do it would be beneficial.
– David
May 11 '15 at 20:53
add a comment |
Beyond attempting to solve the original question, this isn't relevant to the Turbo C issue raised in the original question.
– Sam Storie
May 11 '15 at 20:40
A quick explanation as to why this is the right way to do it would be beneficial.
– David
May 11 '15 at 20:53
Beyond attempting to solve the original question, this isn't relevant to the Turbo C issue raised in the original question.
– Sam Storie
May 11 '15 at 20:40
Beyond attempting to solve the original question, this isn't relevant to the Turbo C issue raised in the original question.
– Sam Storie
May 11 '15 at 20:40
A quick explanation as to why this is the right way to do it would be beneficial.
– David
May 11 '15 at 20:53
A quick explanation as to why this is the right way to do it would be beneficial.
– David
May 11 '15 at 20:53
add a comment |
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7
Turbo C? As in, the 1980s-era C compiler?
– James McNellis
Jul 10 '10 at 23:02
On what line is the compiler reporting problems and/or crashing? You have given no information which might be useful for people to help resolve your problems.
– James McNellis
Jul 10 '10 at 23:03
1
borland turbo c 3 something ..i dont get why i am being taught it in the university :(
– Fahad Uddin
Jul 10 '10 at 23:10
You need to set flag = 1 in
prime, and return it at the end. Or, better, when you find a factor, return 0; if you drop off the end of the loop, return 1. Note that you really only need to go as far as the square root of num to look for factors. This doesn't matter much when you've only fewer than 10 digits in the number, but it really does matter if you have many more digits.– Jonathan Leffler
Jul 10 '10 at 23:41
1
@James: Turbo C was very much in action in academic world till at least 2003 :)
– neal aise
Jul 10 '10 at 23:58