1 #include<iostream> 2 using namespace std; 3 int gcd(int a,int b){ 4     if(a>b){ 5         if(a%b!=0)  return gcd(b,a%b); 6         else  return b; 7     } 8     else gcd(b,a); 9 }10 int main(){11     int a,b;12     while(cin>>a>>b)13     cout<<gcd(a,b)<<endl; 14     return 0;15 }