Codeforces Round 668 (Div. 1)
A
Balanced Bitstring
Codeforces
1500
原题
←B →
翻译中…

A bitstring is a string consisting only of the characters 0 and 1. A bitstring is called $k$-balanced if every substring of size $k$ of this bitstring has an equal amount of 0 and 1 characters ($\frac{k}{2}$ of each).

翻译中…

You are given an integer $k$ and a string $s$ which is composed only of characters 0, 1, and ?. You need to determine whether you can make a $k$-balanced bitstring by replacing every ? characters in $s$ with either 0 or 1.

翻译中…

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

翻译中…

Input

翻译中…

Each test contains multiple test cases. The first line contains the number of test cases $t$ ($1 \le t \le 10^4$). Description of the test cases follows.

翻译中…

The first line of each test case contains two integers $n$ and $k$ ($2 \le k \le n \le 3 \cdot 10^5$, $k$ is even)  — the length of the string and the parameter for a balanced bitstring.

翻译中…

The next line contains the string $s$ ($|s| = n$). It is given that $s$ consists of only 0, 1, and ?.

翻译中…

It is guaranteed that the sum of $n$ over all test cases does not exceed $3 \cdot 10^5$.

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Output

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For each test case, print YES if we can replace every ? in $s$ with 0 or 1 such that the resulting bitstring is $k$-balanced, or NO if it is not possible.

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Note

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For the first test case, the string is already a $4$-balanced bitstring.

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For the second test case, the string can be transformed into 101.

翻译中…

For the fourth test case, the string can be transformed into 0110.

翻译中…

For the fifth test case, the string can be transformed into 1100110.

翻译中…

样例

Input #1
9
6 4
100110
3 2
1?1
3 2
1?0
4 4
????
7 4
1?0??1?
10 10
11??11??11
4 2
1??1
4 4
?0?0
6 2
????00
Output #1
YES
YES
NO
YES
YES
NO
NO
YES
NO
InputCopy OutputCopy
题目信息
题号
1404A
时间限制
2 s
内存限制
256 MB
标签
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。