题解

#include<bits/stdc++.h>
using namespace std;
int f(int a,int b)
{
	if(a%b==0)	return b;
	else return f(b,a%b);
	
}
int main()
{
	int a,b;
	cin>>a>>b;
	cout<<f(a,b);
	return 0;
}