CF1033C.Permutation Game

传统题 时间 2000 ms 内存 256 MiB 8 尝试 25 已通过 9 标签

Permutation Game

After a long day, Alice and Bob decided to play a little game. The game board consists of nn cells in a straight line, numbered from 11 to nn, where each cell contains a number aia_i between 11 and nn. Furthermore, no two cells contain the same number.

A token is placed in one of the cells. They take alternating turns of moving the token around the board, with Alice moving first. The current player can move from cell ii to cell jj only if the following two conditions are satisfied:

  • the number in the new cell jj must be strictly larger than the number in the old cell ii (i.e. aj>aia_j \gt a_i), and
  • the distance that the token travels during this turn must be a multiple of the number in the old cell (i.e. ijmodai=0|i-j|\bmod a_i = 0).

Whoever is unable to make a move, loses. For each possible starting position, determine who wins if they both play optimally. It can be shown that the game is always finite, i.e. there always is a winning strategy for one of the players.

Input

The first line contains a single integer nn (1n1051 \le n \le 10^5) — the number of numbers.

The second line contains nn integers a1,a2,,ana_1, a_2, \ldots, a_n (1ain1 \le a_i \le n). Furthermore, there are no pair of indices iji \neq j such that ai=aja_i = a_j.

Output

Print ss — a string of nn characters, where the ii-th character represents the outcome of the game if the token is initially placed in the cell ii. If Alice wins, then sis_i has to be equal to "A"; otherwise, sis_i has to be equal to "B".

Note

In the first sample, if Bob puts the token on the number (not position):

  • 11: Alice can move to any number. She can win by picking 77, from which Bob has no move.
  • 22: Alice can move to 33 and 55. Upon moving to 55, Bob can win by moving to 88. If she chooses 33 instead, she wins, as Bob has only a move to 44, from which Alice can move to 88.
  • 33: Alice can only move to 44, after which Bob wins by moving to 88.
  • 44, 55, or 66: Alice wins by moving to 88.
  • 77, 88: Alice has no move, and hence she loses immediately.

Samples

8
3 6 5 4 2 7 1 8
BAAAABAB
15
3 11 2 5 10 9 7 13 15 8 4 12 6 1 14
ABAAAABBBAABAAB

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