// GCD : Greatest Common Divisor

​

#include <stdio.h>  

#include <conio.h>  

int GCD_Rec(int num1, int num2);  

int main()  

{  

    int num1, num2;  

    printf( " Enter any two positive numbers \n");  

    scanf("%d %d", &num1, &num2);  

    // call and print the GCD of two number using GCD_Rec()  

    printf(" GCD of two numbers %d and %d is %d", num1, num2, GCD_Rec(num1, num2));  

    return 0;  

}  

int GCD_Rec(int num1, int num2)  

{  

    if (num2 != 0)  

    {  

        return GCD_Rec( num2, num1 % num2);  

    }  

    else  

    {  

        return num1;  

    }  

}  

ll gcd(ll a, ll b)

{

    if (b==0)return a;

    return gcd(b, a % b);   

}

​

#include <stdio.h>

int main()

{

    int n1, n2, i, gcd;

​

    printf("Enter two integers: ");

    scanf("%d %d", &n1, &n2);

​

    for(i=1; i <= n1 && i <= n2; ++i)

    {

        // Checks if i is factor of both integers

        if(n1%i==0 && n2%i==0)

            gcd = i;

    }

​

    printf("G.C.D of %d and %d is %d", n1, n2, gcd);

​

    return 0;

}