Codeforces Round 783 (Div. 1)
B
Optimal Partition
Codeforces
2100
原题
← AC →
翻译中…

You are given an array $a$ consisting of $n$ integers. You should divide $a$ into continuous non-empty subarrays (there are $2^{n-1}$ ways to do that).

翻译中…

Let $s=a_l+a_{l+1}+\ldots+a_r$. The value of a subarray $a_l, a_{l+1}, \ldots, a_r$ is:

翻译中…
  • $(r-l+1)$ if $s \gt 0$,
  • $0$ if $s=0$,
  • $-(r-l+1)$ if $s \lt 0$.
翻译中…

What is the maximum sum of values you can get with a partition?

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Input

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The input consists of multiple test cases. The first line contains a single integer $t$ ($1 \le t \le 5 \cdot 10^5$) — 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 $n$ ($1 \le n \le 5 \cdot 10^5$).

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The second line of each test case contains $n$ integers $a_1$, $a_2$, ..., $a_n$ ($-10^9 \le a_i \le 10^9$).

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

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Output

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For each test case print a single integer — the maximum sum of values you can get with an optimal parition.

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Note

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Test case $1$: one optimal partition is $[1, 2]$, $[-3]$. $1+2 \gt 0$ so the value of $[1, 2]$ is $2$. $-3 \lt 0$, so the value of $[-3]$ is $-1$. $2+(-1)=1$.

翻译中…

Test case $2$: the optimal partition is $[0, -2, 3]$, $[-4]$, and the sum of values is $3+(-1)=2$.

翻译中…

样例

Input #1
5
3
1 2 -3
4
0 -2 3 -4
5
-1 -2 3 -1 -1
6
-1 2 -3 4 -5 6
7
1 -1 -1 1 -1 -1 1
Output #1
1
2
1
6
-1
InputCopy OutputCopy
题目信息
题号
1667B
时间限制
4 s
内存限制
256 MB
标签
数据结构
动态规划

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。