poj 2823

题意：
你去看图就明白了，单调队列模板题

思路：

代码：

#include <cstdio>
#include <iostream>
#include <iomanip>
#include <string>
#include <cstdlib>
#include <cstring>
#include <queue>
#include <set>
#include <vector>
#include <map>
#include <algorithm>
#include <cmath>
#include <stack>

#define INF 0x3f3f3f3f
#define IMAX 2147483646
#define LINF 0x3f3f3f3f3f3f3f3f
#define ll long long
#define ull unsigned long long
#define uint unsigned int

using namespace std;

int n,m, a[1111111], que[1111111], l, r;

int main() {
	scanf("%d%d", &n,&m);
	for (int i = 1; i <= n; i++)
		scanf("%d", a + i);
	l = r = 0;
	for (int i = 1; i <= n; i++) {
		while (r > l&&a[que[r - 1]] >= a[i])r--;
		que[r++] = i;
		if (i >= m)printf("%d ", a[que[l]]);
		if (i - que[l] + 1 >= m)l++;
	}
	printf("\n");
	l = r = 0;
	for (int i = 1; i <= n; i++) {
		while (r > l&&a[que[r - 1]] <= a[i])r--;
		que[r++] = i;
		if (i >= m)printf("%d ", a[que[l]]);
		if (i - que[l] + 1 >= m)l++;
	}
	printf("\n");
	
	return 0;
}