http://cthbstalpha.blogspot.com/2016/05/ZJa024.html

ZJa024.cpp

#include<iostream>
using namespace std ;

int main(){
    int a ,b ;

    while (cin >> a >> b ){
        int ans = 1 ;
        for (int i=2 ;i<=a && i<=b ;i++ ){
            if (a%i==0 && b%i==0){
                ans=i ;
            }
        }

        cout << ans <<endl ;
    }
}