#include <iostream>
using namespace std;
// greedy
// it can be proved that '-1' will not occur
int main(){
    int n, a, g;
    cin >> n;

    int sum {0};
    for(int i = 0; i < n; i ++){
        cin >> a >> g;
        if(sum + a <= 500){
            cout << "A";
            sum += a;
        }else{
            cout << "G";
            sum -= g;
        }
    }
    cout << endl;
    return 0;
}