백준 15565번 귀여운 라이언

import java.io.*;
import java.util.*;

public class Main {
    static FastReader scan = new FastReader();
    static StringBuilder sb = new StringBuilder();

    static int N, K;
    static int[] A;

    static void input() {
        N = scan.nextInt();
        K = scan.nextInt();
        A = new int[N + 1];
        for (int i = 1; i <= N; i++) {
            A[i] = scan.nextInt();
        }
    }

    static void pro() {
        int right = 0, count = 0, answer = -1;
        for (int left = 1; left <= N; left++) {
            while (right < N && count < K) {
                right++;
                if (A[right] == 1) {
                    count++;
                }
            }

            if (count == K) {
                int size = right - left + 1;
                if (answer < 0) {
                    answer = size;
                } else {
                    answer = Math.min(answer, size);
                }
            }

            if (A[left] == 1) {
                count--;
            }
        }

        System.out.println(answer);
    }

    public static void main(String[] args) {
        input();
        pro();
    }


    static class FastReader {
        BufferedReader br;
        StringTokenizer st;

        public FastReader() {
            br = new BufferedReader(new InputStreamReader(System.in));
        }

        public FastReader(String s) throws FileNotFoundException {
            br = new BufferedReader(new FileReader(new File(s)));
        }

        String next() {
            while (st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

        int nextInt() {
            return Integer.parseInt(next());
        }

        long nextLong() {
            return Long.parseLong(next());
        }

        double nextDouble() {
            return Double.parseDouble(next());
        }

        String nextLine() {
            String str = "";
            try {
                str = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return str;
        }
    }
}