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 Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.util.*;
import java.util.stream.Collectors;
import java.io.*;
import java.nio.charset.StandardCharsets;

public class Main {
	int N, K, C;
	char[] S;
	List<Integer> result;

	public static void main(String[] args) throws IOException {
		InputStreamReader reader = new InputStreamReader(System.in, StandardCharsets.UTF_8);
		BufferedReader in = new BufferedReader(reader);
		Main ins = new Main(in);
		ins.calc();
		ins.showResult();
	}

	Main(BufferedReader in) throws IOException {
		String[] tokens = in.readLine().split(" ");
		N = Integer.parseInt(tokens[0]);
		K = Integer.parseInt(tokens[1]);
		C = Integer.parseInt(tokens[2]);
		S = in.readLine().toCharArray();
	}

	List<Integer> searchFromTop(int currentIndex, int remainNum) {
		if (S[currentIndex] == 'o') {
			if (remainNum == 1) {
				List<Integer> result = new ArrayList<>(K);
				result.add(currentIndex);
				return result;
			} else {
				List<Integer> result = searchFromTop(currentIndex + C + 1, remainNum - 1);
				result.add(currentIndex);
				return result;
			}
		} else {
			return searchFromTop(currentIndex + 1, remainNum);
		}
	}

	List<Integer> searchFromEnd(int currentIndex, int remainNum) {
		if (S[currentIndex] == 'o') {
			if (remainNum == 1) {
				List<Integer> result = new ArrayList<>(K);
				result.add(currentIndex);
				return result;
			} else {
				List<Integer> result = searchFromEnd(currentIndex - C - 1, remainNum - 1);
				result.add(currentIndex);
				return result;
			}
		} else {
			return searchFromEnd(currentIndex - 1, remainNum);
		}
	}

	void calc() {
		List<Integer> indexes = searchFromTop(0, K);
		List<Integer> indexes2 = searchFromEnd(N - 1, K);
		Collections.reverse(indexes);
		result = new ArrayList<>();
		for (int i = 0; i < indexes.size(); ++i) {
			if (indexes.get(i).equals(indexes2.get(i))) {
				result.add(indexes.get(i));
			}
		}

	}

	void showResult() {
		for (int i = 0; i < result.size(); ++i) {
			System.out.println((result.get(i) + 1));
		}
	}
}