C Program to Write a recursive C function to calculate the GCD of two numbers - IProgramX

Q. Write a recursive C function to calculate the GCD of two numbers. Use this function in main. The GCD is calculated as : 
gcd(a,b) = a                                if b = 0
              = gcd (b, a mod b)       otherwise 

Program

#include <stdio.h>
int gcd(int, int);
int main()
{
    int a, b, result;
    printf("Enter the two numbers to find their GCD: ");
    scanf("%d%d", &a, &b);
    result = gcd(a, b);
    printf("The GCD of %d and %d is %d.\n", a, b, result);
}

int gcd(int a, int b)
{
    while (a != b)
    {
        if (a > b)
        {
            return gcd(a - b, b);
        }
        else
        {
            return gcd(a, b - a);
        }
    }
    return a;
}

Output:

Enter the two numbers to find their GCD: 24 7
The GCD of 24 and 7 is 1.