func_code_string: #include <bits/stdc++.h>   using namespace std;   long long n, a[100001], b[100001], c[100001], k, x;   int main() {     cin >> n;     for (int i = 1; i <= n; i++) {       cin >> a[i];       b[a[i]] = i;     }     c[b[n]] = 0;     for (long long i = n - 1; i >= 1; i--) {       x = b[i];       for (long long j = (x - 1) % i + 1; j <= n; j += i) {         if (a[j] > i && c[j] == 0) {           c[x] = 1;           break;         }       }     }     for (int i = 1; i <= n; i++) {       if (c[i])         cout <<  A ;       else         cout <<  B ;     }   }   