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: Accepted)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using static System.Console;
using static System.Math;

namespace AtTest.ABC_161
{
    class E
    {
        static void Main(string[] args)
        {
            var sw = new System.IO.StreamWriter(OpenStandardOutput()) { AutoFlush = false };
            SetOut(sw);

            Method(args);

            Out.Flush();
        }

        static void Method(string[] args)
        {
            int[] nkc = ReadInts();
            int n = nkc[0];
            int k = nkc[1];
            int c = nkc[2];
            string s = Read();

            int[] fronts = new int[n];
            for(int i = 0; i < n; i++)
            {
                if (s[i] == 'o')
                {
                    fronts[i] = 1;
                    if (i > 0)
                    {
                        fronts[i] += fronts[i - 1];
                    }
                    int to = i + c + 1;
                    for (int j = i + 1; j < Min(to, n); j++)
                    {
                        fronts[j] = fronts[j - 1];
                    }
                    i = to - 1;
                }
                else if(i>0)
                {
                    fronts[i] = fronts[i - 1];
                }
            }

            int[] backs = new int[n];
            for(int i = n-1; i>=0; i--)
            {
                if (s[i] == 'o')
                {
                    backs[i] = 1;
                    if (i < n - 1)
                    {
                        backs[i] += backs[i + 1];
                    }
                    int to = i - c - 1;
                    for (int j = i - 1; j >= Max(to, 0); j--)
                    {
                        backs[j] = backs[j + 1];
                    }
                    i = to + 1;
                }
                else if (i < n - 1)
                {
                    backs[i] = backs[i + 1];
                }
            }

            for(int i = 0; i < n; i++)
            {
                if (s[i] == 'o')
                {
                    int cnt = 0;
                    if (i > 0)
                    {
                        cnt += fronts[i - 1];
                    }
                    if (i < n - 1)
                    {
                        cnt += backs[i + 1];
                    }
                    if (cnt == k - 1)
                    {
                        WriteLine(i + 1);
                    }
                }
            }
        }

        private static string Read() { return ReadLine(); }
        private static char[] ReadChars() { return Array.ConvertAll(Read().Split(), a => a[0]); }
        private static int ReadInt() { return int.Parse(Read()); }
        private static long ReadLong() { return long.Parse(Read()); }
        private static double ReadDouble() { return double.Parse(Read()); }
        private static int[] ReadInts() { return Array.ConvertAll(Read().Split(), int.Parse); }
        private static long[] ReadLongs() { return Array.ConvertAll(Read().Split(), long.Parse); }
        private static double[] ReadDoubles() { return Array.ConvertAll(Read().Split(), double.Parse); }
    }
}