Codeforces Round 816 (Div. 2)
C
Monoblock
Codeforces
1700
原题
← BD →
翻译中…

Stanley has decided to buy a new desktop PC made by the company "Monoblock", and to solve captcha on their website, he needs to solve the following task.

翻译中…

The awesomeness of an array is the minimum number of blocks of consecutive identical numbers in which the array could be split. For example, the awesomeness of an array

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  • $[1, 1, 1]$ is $1$;
  • $[5, 7]$ is $2$, as it could be split into blocks $[5]$ and $[7]$;
  • $[1, 7, 7, 7, 7, 7, 7, 7, 9, 9, 9, 9, 9, 9, 9, 9, 9]$ is 3, as it could be split into blocks $[1]$, $[7, 7, 7, 7, 7, 7, 7]$, and $[9, 9, 9, 9, 9, 9, 9, 9, 9]$.
翻译中…

You are given an array $a$ of length $n$. There are $m$ queries of two integers $i$, $x$. A query $i$, $x$ means that from now on the $i$-th element of the array $a$ is equal to $x$.

翻译中…

After each query print the sum of awesomeness values among all subsegments of array $a$. In other words, after each query you need to calculate $$\sum\limits_{l = 1}^n \sum\limits_{r = l}^n g(l, r),$$ where $g(l, r)$ is the awesomeness of the array $b = [a_l, a_{l + 1}, \ldots, a_r]$.

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Input

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In the first line you are given with two integers $n$ and $m$ ($1 \leq n, m \leq 10^5$).

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

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In the next $m$ lines you are given the descriptions of queries. Each line contains two integers $i$ and $x$ ($1 \leq i \leq n$, $1 \leq x \leq 10^9$).

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Output

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Print the answer to each query on a new line.

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Note

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After the first query $a$ is equal to $[1, 2, 2, 4, 5]$, and the answer is $29$ because we can split each of the subsegments the following way:

翻译中…
  1. $[1; 1]$: $[1]$, 1 block;
  2. $[1; 2]$: $[1] + [2]$, 2 blocks;
  3. $[1; 3]$: $[1] + [2, 2]$, 2 blocks;
  4. $[1; 4]$: $[1] + [2, 2] + [4]$, 3 blocks;
  5. $[1; 5]$: $[1] + [2, 2] + [4] + [5]$, 4 blocks;
  6. $[2; 2]$: $[2]$, 1 block;
  7. $[2; 3]$: $[2, 2]$, 1 block;
  8. $[2; 4]$: $[2, 2] + [4]$, 2 blocks;
  9. $[2; 5]$: $[2, 2] + [4] + [5]$, 3 blocks;
  10. $[3; 3]$: $[2]$, 1 block;
  11. $[3; 4]$: $[2] + [4]$, 2 blocks;
  12. $[3; 5]$: $[2] + [4] + [5]$, 3 blocks;
  13. $[4; 4]$: $[4]$, 1 block;
  14. $[4; 5]$: $[4] + [5]$, 2 blocks;
  15. $[5; 5]$: $[5]$, 1 block;
翻译中…

which is $1 + 2 + 2 + 3 + 4 + 1 + 1 + 2 + 3 + 1 + 2 + 3 + 1 + 2 + 1 = 29$ in total.

翻译中…

样例

Input #1
5 5
1 2 3 4 5
3 2
4 2
3 1
2 1
2 2
Output #1
29
23
35
25
35
InputCopy OutputCopy
题目信息
题号
1715C
时间限制
1 s
内存限制
256 MB
标签
组合数学
数据结构
模拟
数学

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。