#include <bits/stdc++.h>
using namespace std;
const int MOD = (int)1e9 + 7;
const int INF = (int)1e9;
const long long LINF = (long long)1e18;
const long double PI = acos((long double)-1);
const long double EPS = 1e-9;
long long gcd(long long a, long long b) {
  long long r;
  while (b) {
    r = a % b;
    a = b;
    b = r;
  }
  return a;
}
long long lcm(long long a, long long b) { return a / gcd(a, b) * b; }
long long fpow(long long n, long long k, int p = MOD) {
  long long r = 1;
  for (; k; k >>= 1) {
    if (k & 1) r = r * n % p;
    n = n * n % p;
  }
  return r;
}
template <class T>
void setmin(T& a, T val) {
  if (a > val) a = val;
}
template <class T>
void setmax(T& a, T val) {
  if (a < val) a = val;
}
void addmod(int& a, int val, int p = MOD) {
  if ((a = (a + val)) >= p) a -= p;
}
void submod(int& a, int val, int p = MOD) {
  if ((a = (a - val)) < 0) a += p;
}
int mult(int a, int b, int p = MOD) { return (long long)a * b % p; }
long long inv(int a, int p = MOD) { return fpow(a, p - 2, p); }
const int N = 200005;
int a[N], b[N];
vector<pair<long long, long long> > c;
bool comp(pair<long long, long long> x, pair<long long, long long> y) {
  return (x.first > y.first);
}
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int n;
  cin >> n;
  for (int i = 1; i <= n; i++) {
    cin >> a[i];
    c.push_back(make_pair(a[i], i));
  }
  sort(c.begin(), c.end(), comp);
  for (int i = 0; i < c.size(); i++) {
    int pos = c[i].second, off = c[i].first;
    b[pos] = 2;
    for (int j = pos - off; j >= 1; j -= off) {
      if (a[j] < off) continue;
      if (b[j] == 2) {
        b[pos] = 1;
        break;
      }
    }
    for (int j = pos + off; j <= n; j += off) {
      if (a[j] < off) continue;
      if (b[j] == 2) {
        b[pos] = 1;
        break;
      }
    }
  }
  for (int i = 1; i <= n; i++) {
    if (b[i] == 2)
      cout << "B";
    else
      cout << "A";
  }
  cout << "\n";
  return 0;
}
