Codeforces Round 698 (Div. 1)
B
Nezzar and Binary String
Codeforces
1900
原题
← AC →
翻译中…

Nezzar has a binary string $s$ of length $n$ that he wants to share with his best friend, Nanako. Nanako will spend $q$ days inspecting the binary string. At the same time, Nezzar wants to change the string $s$ into string $f$ during these $q$ days, because it looks better.

翻译中…

It is known that Nanako loves consistency so much. On the $i$-th day, Nanako will inspect a segment of string $s$ from position $l_i$ to position $r_i$ inclusive. If the segment contains both characters '0' and '1', Nanako becomes unhappy and throws away the string.

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After this inspection, at the $i$-th night, Nezzar can secretly change strictly less than half of the characters in the segment from $l_i$ to $r_i$ inclusive, otherwise the change will be too obvious.

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Now Nezzar wonders, if it is possible to avoid Nanako being unhappy and at the same time have the string become equal to the string $f$ at the end of these $q$ days and nights.

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Input

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The first line contains a single integer $t$ ($1 \le t \le 2 \cdot 10^5$) — the number of test cases.

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The first line of each test case contains two integers $n,q$ ($1 \le n \le 2 \cdot 10^5$, $0 \le q \le 2 \cdot 10^5$).

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The second line of each test case contains a binary string $s$ of length $n$.

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The third line of each test case contains a binary string $f$ of length $n$.

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Then $q$ lines follow, $i$-th of them contains two integers $l_i,r_i$ ($1 \le l_i \le r_i \le n$)  — bounds of the segment, that Nanako will inspect on the $i$-th day.

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It is guaranteed that the sum of $n$ for all test cases doesn't exceed $2 \cdot 10^5$, and the sum of $q$ for all test cases doesn't exceed $2 \cdot 10^5$.

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Output

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For each test case, print "YES" on the single line if it is possible to avoid Nanako being unhappy and have the string $f$ at the end of $q$ days and nights. Otherwise, print "NO".

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You can print each letter in any case (upper or lower).

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Note

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In the first test case, $\underline{00000} \rightarrow \underline{000}11 \rightarrow 00111$ is one of the possible sequences of string changes.

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In the second test case, it can be shown that it is impossible to have the string $f$ at the end.

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样例

Input #1
4
5 2
00000
00111
1 5
1 3
2 1
00
01
1 2
10 6
1111111111
0110001110
1 10
5 9
7 10
1 7
3 5
6 10
5 2
10000
11000
2 5
1 3
Output #1
YES
NO
YES
NO
InputCopy OutputCopy
题目信息
题号
1477B
时间限制
2 s
内存限制
512 MB
标签
数据结构
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。