Technocup 2022 - Elimination Round 3
B
Array Eversion
Codeforces
900
原题
← AC →
翻译中…

You are given an array $a$ of length $n$.

翻译中…

Let's define the eversion operation. Let $x = a_n$. Then array $a$ is partitioned into two parts: left and right. The left part contains the elements of $a$ that are not greater than $x$ ($\le x$). The right part contains the elements of $a$ that are strictly greater than $x$ ($ \gt x$). The order of elements in each part is kept the same as before the operation, i. e. the partition is stable. Then the array is replaced with the concatenation of the left and the right parts.

翻译中…

For example, if the array $a$ is $[2, 4, 1, 5, 3]$, the eversion goes like this: $[2, 4, 1, 5, 3] \to [2, 1, 3], [4, 5] \to [2, 1, 3, 4, 5]$.

翻译中…

We start with the array $a$ and perform eversions on this array. We can prove that after several eversions the array $a$ stops changing. Output the minimum number $k$ such that the array stops changing after $k$ eversions.

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Input

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Each test contains multiple test cases. The first line contains the number of test cases $t$ ($1 \le t \le 100$). Description of the test cases follows.

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The first line contains a single integer $n$ ($1 \le n \le 2 \cdot 10^5$).

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The second line contains $n$ integers $a_1, a_2, \dots, a_n$ ($1 \le a_i \le 10^9$).

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It is guaranteed that the sum of $n$ over all test cases does not exceed $2 \cdot 10^5$.

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Output

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For each test case print a single integer $k$ — the number of eversions after which the array stops changing.

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Note

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Consider the fist example.

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  • The first eversion: $a = [1, 4, 2, 5, 3]$, $x = 3$. $[2, 4, 1, 5, 3] \to [2, 1, 3], [4, 5] \to [2, 1, 3, 4, 5]$.
  • The second and following eversions: $a = [2, 1, 3, 4, 5]$, $x = 5$. $[2, 1, 3, 4, 5] \to [2, 1, 3, 4, 5], [] \to [2, 1, 3, 4, 5]$. This eversion does not change the array, so the answer is $1$.
翻译中…

Consider the second example.

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  • The first eversion: $a = [5, 3, 2, 4, 1]$, $x = 1$. $[5, 3, 2, 4, 1] \to [1], [5, 3, 2, 4] \to [1, 5, 3, 2, 4]$.
  • The second eversion: $a = [1, 5, 3, 2, 4]$, $x = 4$. $[1, 5, 3, 2, 4] \to [1, 3, 2, 4], [5] \to [1, 3, 2, 4, 5]$.
  • The third and following eversions: $a = [1, 3, 2, 4, 5]$, $x = 5$. $[1, 3, 2, 4, 5] \to [1, 3, 2, 4, 5], [] \to [1, 3, 2, 4, 5]$. This eversion does not change the array, so the answer is $2$.
翻译中…

样例

Input #1
3
5
2 4 1 5 3
5
5 3 2 4 1
4
1 1 1 1
Output #1
1
2
0
InputCopy OutputCopy
题目信息
题号
1585B
时间限制
1 s
内存限制
256 MB
标签
贪心

题面与样例版权归 Codeforces 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。