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 C# (Mono 4.6.2.0) (judge verdict: Time Limit Exceeded)

using System;
using System.Diagnostics;
using System.IO;
using System.Text;
using System.Linq;
using System.Collections.Generic;

class Program
{
    const string Yes = "Yes";
    const string No = "No";
    const long Mod = 1000000007;
    static void Main(string[] args) {
#if DEBUG
        MyDebugger.Test(process, "../TextFile1.txt");
        //MyDebugger.Test(process, "../TextFile2.txt");
        //MyDebugger.MakeTestCase("../TextFile2.txt");
#else
        object ret = process(new StreamReader(Console.OpenStandardInput()));
        Console.WriteLine(ret);
#endif
    }

    static int[] days;

    static object process(TextReader input) {
        var spl   = input.ReadLine().Split(' ');
        var n     = int.Parse(spl[0]);
        var k     = int.Parse(spl[1]);
        var c     = int.Parse(spl[2]);
        var s = input.ReadLine();

        days = new int[n];

        var r = new List<int>();
        for(int i=0; i<n; i++) {
            //Debug.WriteLine("--" + (i+1) + "--");
            if(days[i] == 0) {
                var se = select(n, k, c, s, i);
                if (!se) r.Add(i);
            }
        }
        //Debug.WriteLine("");

        var buil = new StringBuilder();
        foreach(var i in r) {
            buil.AppendLine((i+1).ToString());
        }
        return buil;
    }

    static bool select(int n, int k, int c, string s, int p) {
        int idx = 0;
        int co = 0;

        var dd = new int[n];

        while (true) {
            if (idx >= n) break;
            if (co >= k) break;

            if (idx == p || s[idx]=='x') {
                idx++;
            } else {
                //Debug.WriteLine(idx+1);
                co++;
                dd[idx] = 1;
                idx += c+1;
            }
        }

        if(co >= k) {
            for(int i=0; i<n; i++) {
                if (dd[i] == 0) days[i] = 1;
            }
            return true;
        } else {
            return false;
        }
    }
}