Problem:
Score : 500 points

Problem Statement

Takahashi has decided to work on K days of his choice from the N days starting with tomorrow.

You are given an integer C and a string S. Takahashi will choose his workdays as follows:

After working for a day, he will refrain from working on the subsequent C days.

If the i-th character of S is x, he will not work on Day i, where Day 1 is tomorrow, Day 2 is the day after tomorrow, and so on.

Find all days on which Takahashi is bound to work.

Constraints

1 \leq N \leq 2 \times 10^5

1 \leq K \leq N

0 \leq C \leq N

The length of S is N.

Each character of S is o or x.

Takahashi can choose his workdays so that the conditions in Problem Statement are satisfied.

Input

Input is given from Standard Input in the following format:

N K C
S

Output

Print all days on which Takahashi is bound to work in ascending order, one per line.

Sample Input 1

11 3 2
ooxxxoxxxoo

Sample Output 1

6

Takahashi is going to work on 3 days out of the 11 days. After working for a day, he will refrain from working on the subsequent 2 days.

There are four possible choices for his workdays: Day 1,6,10, Day 1,6,11, Day 2,6,10, and Day 2,6,11.

Thus, he is bound to work on Day 6.

Sample Input 2

5 2 3
ooxoo

Sample Output 2

1
5

There is only one possible choice for his workdays: Day 1,5.

Sample Input 3

5 1 0
ooooo

Sample Output 3

There may be no days on which he is bound to work.

Sample Input 4

16 4 3
ooxxoxoxxxoxoxxo

Sample Output 4

11
16

Solution in Rust (1.15.1) (judge verdict: Accepted)

use std::io::*;
use std::str::FromStr;

fn read<T: FromStr>() -> T {
    let stdin = stdin();
    let stdin = stdin.lock();
    let token: String = stdin
        .bytes()
        .map(|c| c.expect("failed to read char") as char) 
        .skip_while(|c| c.is_whitespace())
        .take_while(|c| !c.is_whitespace())
        .collect();
    token.parse().ok().expect("failed to parse token")
}

fn main() {
    let n: usize = read();
    let k: usize = read();
    let c: usize = read();

    let s: String = read();
    let ci: Vec<char> = s.chars().collect();

    let mut l = vec![0; k+1];
    let mut r = vec![0; k+1];

    let mut i = 0;
    let mut cnt = 0;
    while i < n && cnt < k {
        if ci[i] == 'o' {
            cnt += 1;
            l[cnt] = i+1;
            i += c+1;
        } else {
            i += 1;
        }
    }
    // println!("{:?}", l);

    let mut i: i32 = n as i32 - 1;
    let mut cnt = k + 1;
    while i >= 0 && cnt > 0 {
        if ci[i as usize] == 'o' {
            cnt -= 1;
            r[cnt] = i as usize + 1;
            i -= c as i32 + 1;
        } else {
            i -= 1;
        }
    }
    // println!("{:?}", r);

    for i in 1..k+1 {
        if l[i] == r[i] {
            println!("{}", l[i]);
        }
    }
}