#include <bits/stdc++.h>
using namespace std;
int a[1000006], g[1000006];
char str[1000006];
int sum1 = 0, sum2 = 0;
int main() {
  int n, i;
  scanf(" %d", &n);
  for (i = 0; i < n; i++) {
    scanf(" %d %d", &a[i], &g[i]);
  }
  for (i = 0; i < n; i++) {
    int c = sum2 - (sum1 + a[i]);
    int d = sum1 - (sum2 + g[i]);
    if (c < 0) c = -c;
    if (d < 0) d = -d;
    if (c < d) {
      str[i] = 'A';
      sum1 = sum1 + a[i];
    } else {
      str[i] = 'G';
      sum2 = sum2 + g[i];
    }
  }
  str[i] = '\n';
  printf("%s\n", str);
  return 0;
}
