题解

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