Codeforces 738D. Sea Battle 模拟

D. Sea Battle

time limit per test：

1 second

memory limit per test

：256 megabytes

input：

standard input

output：

standard output

Galya is playing one-dimensional Sea Battle on a 1 × n grid. In this game a ships are placed on the grid. Each of the ships consists of bconsecutive cells. No cell can be part of two ships, however, the ships can touch each other.

Galya doesn't know the ships location. She can shoot to some cells and after each shot she is told if that cell was a part of some ship (this case is called "hit") or not (this case is called "miss").

Galya has already made k shots, all of them were misses.

Your task is to calculate the minimum number of cells such that if Galya shoot at all of them, she would hit at least one ship.

It is guaranteed that there is at least one valid ships placement.

Input

The first line contains four positive integers n, a, b, k (1 ≤ n ≤ 2·105, 1 ≤ a, b ≤ n, 0 ≤ k ≤ n - 1) — the length of the grid, the number of ships on the grid, the length of each ship and the number of shots Galya has already made.

The second line contains a string of length n, consisting of zeros and ones. If the i-th character is one, Galya has already made a shot to this cell. Otherwise, she hasn't. It is guaranteed that there are exactly k ones in this string.

Output

In the first line print the minimum number of cells such that if Galya shoot at all of them, she would hit at least one ship.

In the second line print the cells Galya should shoot at.

Each cell should be printed exactly once. You can print the cells in arbitrary order. The cells are numbered from 1 to n, starting from the left.

If there are multiple answers, you can print any of them.

Examples

input

5 1 2 1
00100

output

2
4 2

input

13 3 2 3
1000000010001

output

2
7 11

Note

There is one ship in the first sample. It can be either to the left or to the right from the shot Galya has already made (the "1" character). So, it is necessary to make two shots: one at the left part, and one at the right part.

 题目链接：http://codeforces.com/contest/738/problem/D

 题意：有一个长度为n的01串，现在有a艘长度为b的飞船停在0上面，飞船长度是连续的，并且一个0上面最多只能有1艘飞船。求最少打击多少个位置能够打击到一个飞船。

思路：模拟题。每b个连续的0就要打击一次。直至剩下的打击数量为a-1。

代码：

#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
const int MAXN=2e5+100;
int ans[MAXN];
int main()
{
    int n,a,b,k;
    char ch;
    scanf("%d%d%d%d",&n,&a,&b,&k);
    getchar();
    int sign=0;
    int i,j=0;
    for(i=1; i<=n; i++)
    {
        scanf("%c",&ch);
        if(ch=='0')
        {
            sign++;
            if(sign%b==0) ans[j++]=i;
        }
        else sign=0;
    }
    cout<<j-(a-1)<<endl;
    for(i=0; i<j-(a-1); i++) cout<<ans[i]<<" ";
    cout<<endl;
    return 0;
}