#include <iostream>
using namespace std;
 
int findgcd(int a, int b){
//continue loop as long as both a and b are greater then 0
	while(a>0 && b>0){
 
//update a to the remainder of a when divided by b
		if(a>b){
			a = a%b;
		}else{
//else update b to the remainder of b divided by a
			b = b%a;
		}
	}
 
//check if a becomes 0, if so return b as the gcd
	if(a == 0){
		return b;
	}
 
	return a;
 
}
 
int main() {
 
	int n1, n2; 
 
	cin>>n1>>n2;
 
	int gcd = findgcd(n1, n2);
 
	cout<<gcd<<endl;
 
	return 0;
}

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