C Program to find HCF/GCD of two numbers

Definition of HCF (Highest common factor):

HFC is also called greatest common divisor (gcd). HCF of two numbers is a largest positive numbers which can divide both numbers without any remainder.  For example HCF of two numbers 4 and 8 is 2 since 2 is the largest positive number which can dived 4 as well as 8 without a remainder. 

Logic of HCF or GCD of any two numbers:

In HCF we try to find any largest number which can divide both the number.

For example: HCF or GCD of 20 and 30

Both number 20 and 30 are divisible by 1, 2,5,10.

HCF=max (1, 2, 3, 4, 10) =10

#include<stdio.h>

int main(){

    int x,y,m,i;

    printf("Insert any two number: ");

    scanf("%d%d",&x,&y);

    if(x>y)

         m=y;

    else

         m=x;

    for(i=m;i>=1;i--)

    {

         if(x%i==0 && y%i==0)

        {

             printf("\nHCF of two number is : %d",i) ;

             break;

         }

    }

    return 0;

}