102293: [AtCoder]ABC229 D - Longest X

Problem Statement

Given is a string $S$ consisting of X and ..

You can do the following operation on $S$ between $0$ and $K$ times (inclusive).

• Replace a . with an X.

What is the maximum possible number of consecutive Xs in $S$ after the operations?

Constraints

• $1 \leq |S| \leq 2 \times 10^5$
• Each character of $S$ is X or ..
• $0 \leq K \leq 2 \times 10^5$
• $K$ is an integer.

Input

Input is given from Standard Input in the following format:

$S$
$K$

Output

Print the answer.

Sample Input 1

XX...X.X.X.
2

Sample Output 1

5

After replacing the Xs at the $7$-th and $9$-th positions with X, we have XX...XXXXX., which has five consecutive Xs at $6$-th through $10$-th positions.
We cannot have six or more consecutive Xs, so the answer is $5$.

Sample Input 2

XXXX
200000

Sample Output 2

4

It is allowed to do zero operations.

问题描述

给定一个由X和.组成的字符串$S$。

你可以对$S$进行0到$K$次（包括0次和$K$次）以下操作：

• 将一个.替换为X。

操作后，$S$中连续的X的最大可能数量是多少？

约束

• $1 \leq |S| \leq 2 \times 10^5$
• $S$的每个字符是X或.。
• $0 \leq K \leq 2 \times 10^5$
• $K$是一个整数。

输入

输入以标准输入的以下格式给出：

$S$
$K$

输出

打印答案。

样例输入1

XX...X.X.X.
2

样例输出1

5

将第7个和第9个位置的X替换为X后，我们得到XX...XXXXX.，其中在第6个到第10个位置有5个连续的X。
我们不能有6个或更多的连续X，所以答案是5。

样例输入2

XXXX
200000

样例输出2

4

允许进行0次操作。