将yxc大佬的题解用deque写了一遍

#include <bits/stdc++.h>
using namespace std;

const int MAXN = 1e6 + 10;
int a[MAXN];
deque < int > q;//q存放编号 

int main()
{
    int n, k;
    cin >> n >> k;
    for (int i = 1; i <= n; i++)
        cin >> a[i];

    q.clear();
    //单调递增 求最小值
    for (int i = 1; i <= n; i++)
    {
        while (!q.empty() && a[q.back()] >= a[i]) q.pop_back();
        q.push_back(i);
        while (!q.empty() && i - k >= q.front()) q.pop_front();
        if (i >= k) cout << a[q.front()] << " ";
    }
    cout << endl;
    q.clear();
    for (int i = 1; i <= n; i++)
    {
        while (!q.empty() && a[q.back()] <= a[i]) q.pop_back();
        q.push_back(i);
        while (!q.empty() && i - k >= q.front()) q.pop_front();
        if (i >= k) cout << a[q.front()] << " ";
    }
    cout << endl;
    return 0;
}