Program to find GCD(Greatest common divisior) of two numbers using recursion

#include <iostream>
using namespace std; 

int gcd(int a, int b)
{
 if(b == 0)
 {
         return a;
 }
 else
 {
  return gcd(b, a % b);
 }
}

int main()
{
     int a,b;
          
     cout << "Input first number: ";
     cin >> a;
     cout << "Input second number: ";
     cin >> b;
     
     cout << "Greatest common divisior (GCD) is " << gcd(a,b) << endl;
     return 0;
}