挑战程序竞赛系列（54）：4.4 双端队列（1）

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.StringTokenizer;

public class Main{

    String INPUT = "./data/judge/201709/P2823.txt";

    public static void main(String[] args) throws IOException {
        new Main().run();
    }

    static final int MAX_N = 1000000 + 16;

    int N, K;
    int[] nums = new int[MAX_N];
    int[] deq  = new int[MAX_N];
    void solve() {
        N = ni();
        K = ni();
        for (int i = 0; i < N; ++i) nums[i] = ni();
        int[] val = new int[MAX_N];
        int s = 0, t = 0;
        for (int i = 0; i < N; ++i) {
            while ((t - s) > 0 && nums[i] <= nums[deq[t - 1]]) {
                t--;
            }
            deq[t++] = i;

            if (i - K + 1 >= 0) {
                val[i - K + 1] = nums[deq[s]];
                if (deq[s] == i - K + 1) {
                    s++;
                }
            }
        }

        for (int i = 0; i < N - K + 1; ++i) {
            out.print(val[i] + (i + 1 == N - K + 1 ? "\n" : " "));
        }

        s = 0;
        t = 0;
        for (int i = 0; i < N; ++i) {
            while (t > s && nums[i] >= nums[deq[t - 1]]) {
                t--;
            }
            deq[t++] = i;

            if (i - K + 1 >= 0) {
                val[i - K + 1] = nums[deq[s]];
                if (deq[s] == i - K + 1) {
                    s++;
                }
            }
        }

        for (int i = 0; i < N - K + 1; ++i) {
            out.print(val[i] + (i + 1 == N - K + 1 ? "\n" : " "));
        }
    }

    FastScanner in;
    PrintWriter out;

    void run() throws IOException {
        boolean oj;
        try {
            oj = ! System.getProperty("user.dir").equals("F:\\java_workspace\\leetcode");
        } catch (Exception e) {
            oj = System.getProperty("ONLINE_JUDGE") != null;
        }

        InputStream is = oj ? System.in : new FileInputStream(new File(INPUT));
        in = new FastScanner(is);
        out = new PrintWriter(System.out);
        long s = System.currentTimeMillis();
        solve();
        out.flush();
        if (!oj){
            System.out.println("[" + (System.currentTimeMillis() - s) + "ms]");
        }
    }

    public boolean more(){
        return in.hasNext();
    }

    public int ni(){
        return in.nextInt();
    }

    public long nl(){
        return in.nextLong();
    }

    public double nd(){
        return in.nextDouble();
    }

    public String ns(){
        return in.nextString();
    }

    public char nc(){
        return in.nextChar();
    }

    class FastScanner {
        BufferedReader br;
        StringTokenizer st;
        boolean hasNext;

        public FastScanner(InputStream is) throws IOException {
            br = new BufferedReader(new InputStreamReader(is));
            hasNext = true;
        }

        public String nextToken() {
            while (st == null || !st.hasMoreTokens()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (Exception e) {
                    hasNext = false;
                    return "##";
                }
            }
            return st.nextToken();
        }

        String next = null;
        public boolean hasNext(){
            next = nextToken();
            return hasNext;
        }

        public int nextInt() {
            if (next == null){
                hasNext();
            }
            String more = next;
            next = null;
            return Integer.parseInt(more);
        }

        public long nextLong() {
            if (next == null){
                hasNext();
            }
            String more = next;
            next = null;
            return Long.parseLong(more);
        }

        public double nextDouble() {
            if (next == null){
                hasNext();
            }
            String more = next;
            next = null;
            return Double.parseDouble(more);
        }

        public String nextString(){
            if (next == null){
                hasNext();
            }
            String more = next;
            next = null;
            return more;
        }

        public char nextChar(){
            if (next == null){
                hasNext();
            }
            String more = next;
            next = null;
            return more.charAt(0);
        }
    }

    static class ArrayUtils {

        public static void fill(int[][] f, int value) {
            for (int i = 0; i < f.length; ++i) {
                Arrays.fill(f[i], value);
            }
        }

        public static void fill(int[][][] f, int value) {
            for (int i = 0; i < f.length; ++i) {
                fill(f[i], value);
            }
        }

        public static void fill(int[][][][] f, int value) {
            for (int i = 0; i < f.length; ++i) {
                fill(f[i], value);
            }
        }
    }
}