Is my code for gcd function valid?

[MathematicalPhysicist]

i have to write the function gcd for c programme.
here's my code:

int gcd(int m, int n)
{
 int s,r,x,y;
 
 if (m>=n)
  {
    r=m-(m/n)*n;
    for(x=m,y=n;r!=0;x=y,y=r)
     r=x-(x/y)*y;
   }
  if(n>m)
  {
    r=n-(n/m)*n;
  for(x=n,y=m;r!=0;x=y,y=r)
      r=x-(x/y)*y;
 }
return(r);
}

so is this correct? I am using the fact that the divison of two integers returns an integer solution, i.e without the remainder, and ofcourse euclid's algorithm.
p.s
this is a part of a programme that i need to do in order to check for pythaogrean triplets, so it's not supposed to run alone.

thanks in advance.

 

[MathematicalPhysicist]

int gcd(int m, int n)
{
 int s,r,x,y;
 
 if (m>=n)
  {
    r=m-(m/n)*n;
    for(x=m,y=n;r!=0;x=y,y=r)
     {
      s=r;
     r=x-(x/y)*y;
      }
   }
  if(n>m)
  {
    r=n-(n/m)*n;
  for(x=n,y=m;r!=0;x=y,y=r)
      {
      s=r;
      r=x-(x/y)*y;
      }
 }
return(s);
}

i think that now it works ok, what do you think?

 

[ranger]

Yea, its working. But you need to add a case that covers when there is no remainder. Like when I do 10 and 5, the program returns 0 as the gcd.

Heres a stand alone program that I wrote, utilizing the modulus function.

/ * Euclid's method of finding the greatest common divisor of two integers*/
#include <stdio.h>

int gcd(int num1, int num2);
int swap(int *pa, int *pb);

int main()
{
	int m,n,gcd_num;
	
	printf("Enter two integers\n");
	scanf("%d %d", &m, &n);
	if(m <= 0 || n <= 0) {
		printf("Zero input detected\n");
		exit(1);
	}
	if(m <= n) swap(&m, &n);
	gcd_num = gcd(m,n);
	printf("\nThe greatest common divisor of %d and %d is %d\n",m,n,gcd_num);
	return 0;
}

int swap(int *pa, int *pb)
{
	int temp = *pa;
	*pa = *pb;
	*pb = temp;
	return;
}

int gcd(int m, int n)
{
	int r;
	
	[b]if(m%n == 0)
	r = n;[/b]
	
	while((m%n!=0))
	{
   	r = m%n;
   	printf("Trying %d\n",r);
	m=n;
	n=r;
	}
	return r;
}

The bold lines takes care of the case when there is no remainder.

 

[MathematicalPhysicist]

now i need to write a programme that will get as input, 'n' and 'max' it should look on triples such that 1<=a<b<c<=max and check wether they satisfy a^n+b^n=c^n, if so the triple will be printed, and at the end there will be printed the number of triples.
i need no duplicates of triples such as: 3,4,5 or 4,3,5 which are the same and that gcd(a,b)=1.
now he i wrote the programme, but I am finding difficult where to put the condition that a<b<c, here's what i did so far:

#include <stdio.h>
int gcd(int m,int n)
{
  int r,s,x,y;
  if(m>=n){
    r=m-(m/n)*n;
    if(r==0)
      s=n;
  for(x=m,y=n;r!=0;x=y,y=r)
     {
       s=r;
       r=x-(x/y)*y;       
     }
    
  }
  if(n>m){
    r=n-(n/m)*m;
    if(r==0)
      s=m;
    for(x=m,y=n;r!=0;x=y,y=r)
     {
       s=r;
       r=x-(x/y)*y;      
     }
  }
return(s);
}
int pow(int a, int t)
{
  int q,p;
    for(p=1,q=1;q<=t;q++)
      p=a*p;

return(p);
}
main()
{
  int d,f=0,n,max,a,b,c;
 printf("insert the degree you wish to check for n-th pythogrean triplets\n");
 scanf("%d", &n);
 printf("insert the maximal number you want to check for\n");
 scanf("%d", &max);
 if(max>2){
   
   for(a=1;a<=max;a++)
     {
       for(b=2;b<=max;b++)
         {
   for(c=3;a<b,b<c,c<=max;c++)
     {
       if((pow(a,n)+pow(b,n)==pow(c,n))&& gcd(a,b)==1){
         f++;
         printf("the triplet is: %d, %d, %d \n", a,b,c);
       }
       if(pow(a,n)+pow(b,n)==pow(c,n)&& (gcd(a,b))!=1){
         f++;
          printf("the triplet is: %f, %f, %f \n", a/(gcd(a,b)),b/(gcd(a,b)),c/(gcd(a,b)));
       }
     }
         }
     }
 }

    
     

       if(max<=2)
        printf("there isn't such triplet \n");
 printf("the number of triplets in the specified domain is: %d \n", f);
 }

any hints where should i put this condition, i put it in the third loop, but it doesn't seem to work.
your help is appreciated.

 

[MathematicalPhysicist]

here's an abbreviated code, without specifting the gcd and pow functions:

  int d,f=0,n,max,a,b,c;
 printf("insert the degree you wish to check for n-th pythogrean triplets\n");
 scanf("%d", &n);
 printf("insert the maximal number you want to check for\n");
 scanf("%d", &max);
 if(max>2){
   
   for(a=1;a<=max;a++)
     {
       for(b=2;b<=max;b++)
         {
   for(c=3;a<b,b<c,c<=max;c++)
     {
       if((pow(a,n)+pow(b,n)==pow(c,n))&& gcd(a,b)==1){
         f++;
         printf("the triplet is: %d, %d, %d \n", a,b,c);
       }
       if(pow(a,n)+pow(b,n)==pow(c,n)&& (gcd(a,b))!=1){
         f++;
          printf("the triplet is: %f, %f, %f \n", a/(gcd(a,b)),b/(gcd(a,b)),c/(gcd(a,b)));
       }
     }
         }
     }
 }

    
     

       if(max<=2)
        printf("there isn't such triplet \n");
 printf("the number of triplets in the specified domain is: %d \n", f);
 }

i hope someone can give me some hint.