EPIC Institute of Technology Round Summer 2024 (Div. 1 + Div. 2)
B
K-Sort
Codeforces
1000
原题
← AC →
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You are given an array of integers $a$ of length $n$.

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You can apply the following operation any number of times (maybe, zero):

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  • First, choose an integer $k$ such that $1 \le k \le n$ and pay $k + 1$ coins.
  • Then, choose exactly $k$ indices such that $1 \le i_1 \lt i_2 \lt \ldots \lt i_k \le n$.
  • Then, for each $x$ from $1$ to $k$, increase $a_{i_x}$ by $1$.
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Find the minimum number of coins needed to make $a$ non-decreasing. That is, $a_1 \le a_2 \le \ldots \le a_n$.

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Input

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Each test contains multiple test cases. The first line of input contains a single integer $t$ ($1 \le t \le 10^4$) — the number of test cases. The description of the test cases follows.

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The first line of each test case contains a single integer $n$ ($1 \le n \le 10^5$) — the length of the array $a$.

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The second line of each test case contains $n$ integers $a_1, a_2, \ldots, a_n$ ($1 \le a_i \le 10^9$) — the elements of the array $a$.

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

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Output

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For each test case, output a single integer — the minimum number of coins needed to make $a$ non-decreasing.

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Note

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In the first test case, $a$ is already sorted, so you don't have to spend any coins.

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In the second test case, the optimal sequence of operations is:

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  • Choose $k = 2$ and the indices $2$ and $5$: $[ 2, \color{red}{1}, 4, 7, \color{red}{6} ] \rightarrow [2, 2, 4, 7, 7]$. This costs $3$ coins.
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It can be proven that it is not possible to make $a$ non-decreasing by spending less than $3$ coins.

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样例

Input #1
5
3
1 7 9
5
2 1 4 7 6
4
1 3 2 4
1
179
9
344 12 37 60 311 613 365 328 675
Output #1
0
3
2
0
1821
InputCopy OutputCopy
题目信息
题号
1987B
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。