Quizzes

AtCoder

IDabc184_b

Time2000ms

Memory256MB

Difficulty—

Takahashi will answer $N$ quiz questions. Initially, he has $X$ points. Each time he answers a question, he gains $1$ point if his answer is correct and loses $1$ point if it is incorrect. However, there is an exception: when he has $0$ points, he loses nothing for answering a question incorrectly. You will be given a string $S$ representing whether Takahashi's answers are correct. If the $i$\-th character of $S$ from the left is `o`, it means his answer for the $i$\-th question is correct; if that character is `x`, it means his answer for the $i$\-th question is incorrect. How many points will he have in the end? ## Constraints * $1 \le N \le 2 \times 10^5$ * $0 \le X \le 2 \times 10^5$ * $S$ is a string of length $N$ consisting of `o` and `x`. ## Input Input is given from Standard Input in the following format: $N$ $X$ $S$ [samples]

Samples

Input #1

3 0
xox

Output #1

0

Initially, he has $0$ points.  
He answers the first question incorrectly but loses nothing because he has no point.  
Then, he answers the second question correctly, gains $1$ point, and now has $1$ point.  
Finally, he answers the third question incorrectly, loses $1$ point, and now has $0$ points.  
Thus, he has $0$ points in the end. We should print $0$.

Input #2

20 199999
oooooooooxoooooooooo

Output #2

Input #3

20 10
xxxxxxxxxxxxxxxxxxxx

Output #3

API Response (JSON)

{
  "problem": {
    "name": "Quizzes",
    "description": {
      "content": "Takahashi will answer $N$ quiz questions.   Initially, he has $X$ points. Each time he answers a question, he gains $1$ point if his answer is correct and loses $1$ point if it is incorrect.   However",
      "description_type": "Markdown"
    },
    "platform": "AtCoder",
    "limit": {
      "time_limit": 2000,
      "memory_limit": 262144
    },
    "difficulty": "None",
    "is_remote": true,
    "is_sync": true,
    "sync_url": null,
    "sign": "abc184_b"
  },
  "statements": [
    {
      "statement_type": "Markdown",
      "content": "Takahashi will answer $N$ quiz questions.  \nInitially, he has $X$ points. Each time he answers a question, he gains $1$ point if his answer is correct and loses $1$ point if it is incorrect.  \nHowever...",
      "is_translate": false,
      "language": "English"
    }
  ]
}

Full JSON Raw Segments