how to find gcd of two numbers in c++ code example

Example 1: gcd in c++

#include<iostream>
using namespace std;
long long gcd(long long a, long long b) 
{ 
    if (b == 0) 
        return a; 
    return gcd(b, a % b);  
      
} 
int main()
{
	long long a,b;
	cin>>a>>b;
	cout<<gcd(a,b);
}

Example 2: gcd of two numbers c++

// gcd function definition below:
int gcd(int a, int b) {
   if (b == 0)
   return a;
   return gcd(b, a % b);
}

int a = 105, b = 30;
cout<<"GCD of "<< a <<" and "<< b <<" is "<< gcd(a, b);
// output = "GCD of 105 and 30 is 15";