欧几里得

C++ 代码

#include<iostream>

using namespace std;

int gcd(int a,int b){
  return b? gcd(b,a%b):a;
}
int main(){
    int n;
    cin>>n;
    while(n--){
        int a,b;
        cin>>a>>b;

        cout<<gcd(a,b)<<endl;
    }

    return 0;
}