Codeforces Round 882 (Div. 2)
D
Professor Higashikata
Codeforces
1900
原题
← CE →
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Josuke is tired of his peaceful life in Morioh. Following in his nephew Jotaro's footsteps, he decides to study hard and become a professor of computer science. While looking up competitive programming problems online, he comes across the following one:

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Let $s$ be a binary string of length $n$. An operation on $s$ is defined as choosing two distinct integers $i$ and $j$ ($1 \leq i \lt j \leq n$), and swapping the characters $s_i, s_j$.

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Consider the $m$ strings $t_1, t_2, \ldots, t_m$, where $t_i$ is the substring $^\dagger$ of $s$ from $l_i$ to $r_i$. Define $t(s) = t_1+t_2+\ldots+t_m$ as the concatenation of the strings $t_i$ in that order.

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There are $q$ updates to the string. In the $i$-th update $s_{x_i}$ gets flipped. That is if $s_{x_i}=1$, then $s_{x_i}$ becomes $0$ and vice versa. After each update, find the minimum number of operations one must perform on $s$ to make $t(s)$ lexicographically as large$^\ddagger$ as possible.

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Note that no operation is actually performed. We are only interested in the number of operations.

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Help Josuke in his dream by solving the problem for him.

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——————————————————————

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$\dagger$ A string $a$ is a substring of a string $b$ if $a$ can be obtained from $b$ by the deletion of several (possibly, zero or all) characters from the beginning and several (possibly, zero or all) characters from the end.

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$\ddagger$ A string $a$ is lexicographically larger than a string $b$ of the same length if and only if the following holds:

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  • in the first position where $a$ and $b$ differ, the string $a$ has a $1$, and the string $b$ has a $0$.
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Input

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The first line contains three integers $n$, $m$, $q$ ($1 \leq n,m,q \leq 2 \cdot 10^5$).

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The next line contains a binary string $s$ of length $n$, consisting only of digits $0$ and $1$.

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The $i$-th line of the next $m$ lines contains two integers $l_i$ and $r_i$ ($1 \leq l_i \leq r_i \leq n$).

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The $i$-th line of the next $q$ lines contains a single integer $x_i$ ($1 \leq x_i \leq n$).

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Output

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Print $q$ integers. The $i$-th integer is the minimum number of operations that need to be performed on $s$ to get the lexicographically largest possible string $t(s)$ in the $i$-th round.

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Note

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In the first test case,

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Originally, $t(s) = s(1,2) + s(1,2) = 0101$.

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After the $1$-st query, $s$ becomes $11$ and consequently $t$ becomes $1111$. You don't need to perform any operation as $t(s)$ is already the lexicographically largest string possible.

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After the $2$-nd query, $s$ becomes $01$ and consequently $t$ becomes $0101$. You need to perform $1$ operation by swapping $s_1$ and $s_2$. Consequently, $t(s)$ becomes $1010$ which is the lexicographically largest string you can achieve.

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样例

Input #1
2 2 4
01
1 2
1 2
1
1
2
2
Output #1
0
1
0
1
InputCopy OutputCopy
Input #2
8 6 10
10011010
5 6
2 3
6 8
5 7
5 8
6 8
3
5
6
2
5
2
5
8
4
1
Output #2
2
3
2
2
1
2
2
2
2
2
InputCopy OutputCopy
题目信息
题号
1847D
时间限制
2 s
内存限制
256 MB
标签
数据结构
并查集
贪心
模拟
字符串

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。