CF1860C.Game on Permutation

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题目描述

Alice and Bob are playing a game. They have a permutation pp of size nn (a permutation of size nn is an array of size nn where each element from 11 to nn occurs exactly once). They also have a chip, which can be placed on any element of the permutation.

Alice and Bob make alternating moves: Alice makes the first move, then Bob makes the second move, then Alice makes the third move, and so on. During the first move, Alice chooses any element of the permutation and places the chip on that element. During each of the next moves, the current player has to move the chip to any element that is simultaneously to the left and strictly less than the current element (i. e. if the chip is on the ii -th element, it can be moved to the jj -th element if j<ij < i and pj<pip_j < p_i ). If a player cannot make a move (it is impossible to move the chip according to the rules of the game), that player wins the game.

Let's say that the ii -th element of the permutation is lucky if the following condition holds:

  • if Alice places the chip on the ii -th element during her first move, she can win the game no matter how Bob plays (i. e. she has a winning strategy).

You have to calculate the number of lucky elements in the permutation.

输入格式

The first line contains a single integer tt ( 1t1041 \le t \le 10^4 ) — the number of test cases.

The first line of each test case contains a single integer nn ( 1n31051 \le n \le 3 \cdot 10^5 ) – the number of elements in the permutation.

The second line contains nn integers p1,p2,,pnp_1, p_2, \dots, p_n ( 1pin1 \le p_i \le n ). All pip_i are distinct.

The sum of nn over all test cases doesn't exceed 31053 \cdot 10^5 .

输出格式

For each test case, print a single integer — the number of lucky elements in the permutation.

输入输出样例

  • 输入#1

    4
    3
    2 1 3
    2
    2 1
    3
    1 2 3
    4
    2 1 4 3

    输出#1

    1
    0
    1
    2

说明/提示

In the first test case of the example, the 33 -rd element of the permutation is lucky.

In the second test case of the example, there are no lucky elements.

In the third test case of the example, the 22 -nd element of the permutation is lucky.

In the fourth test case of the example, the 33 -rd and the 44 -th element of the permutation are lucky.

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