gcd of two numbers c 2b 2b

1// gcd function definition below:
2int gcd(int a, int b) {
3   if (b == 0)
4   return a;
5   return gcd(b, a % b);
6}
7
8int a = 105, b = 30;
9cout<<"GCD of "<< a <<" and "<< b <<" is "<< gcd(a, b);
10// output = "GCD of 105 and 30 is 15";

1#include<iostream>
2using namespace std;
3long long gcd(long long a, long long b) 
4{ 
5    if (b == 0) 
6        return a; 
7    return gcd(b, a % b);  
8      
9} 
10int main()
11{
12	long long a,b;
13	cin>>a>>b;
14	cout<<gcd(a,b);
15}

1int gcd(int a, int b) 
2{ 
3    // Everything divides 0  
4    if (a == 0) 
5       return b; 
6    if (b == 0) 
7       return a; 
8    // base case 
9    if (a == b) 
10        return a; 
11    // a is greater 
12    if (a > b) 
13        return gcd(a-b, b); 
14    return gcd(a, b-a); 
15}