Mike is the president of country What-The-Fatherland. There are n n bears living in this country besides Mike. All of them are standing in a line and they are numbered from 1 1 to n n from left to right. i -th bear is exactly ai feet high.
A group of bears is a non-empty contiguous segment of the line. The size of a group is the number of bears in that group. The strength of a group is the minimum height of the bear in that group.

Mike is a curious to know for each x x such that 1<=x<=n the maximum strength among all groups of size x .
The first line of input contains integer n (1<=n<=2×10 ^5), the number of bears.

The second line contains n n integers separated by space,a1,a2,…,an(1<=ai <=10 ^9), heights of bears.

输出格式:
Print n n integers in one line. For each x x from 1 1 to n n , print the maximum strength among all groups of size x .

题意:有一个长度为n的序列,序列有长度为1…n的连续子序列,一个连续子序列里面最小的值称作这个子序列的子序列的strength,
要求出每种长度的连续子序列的最大的strength。
思路:可以用单独栈求出每个点的L[i],R[i],以当前点为最小值的左右边界
然后排序一遍(按值排序)时间复杂度为排序复杂度(nlogn)

#include <bits/stdc++.h>
using namespace std;
const int maxn = 2e5 + 5;
int L[maxn], R[maxn], a[maxn];
stack<int> s;
struct node {
	int w, len;
}b[maxn];
int ans[maxn];
bool cmp(node a, node b) {
	return a.w > b.w;
}

int main() {
	int n;
	scanf("%d", &n);
	for (int i = 1; i <= n; i++) {
		scanf("%d", &a[i]);
	}
	a[0] = 0; a[n + 1] = 0;
	for (int i = 1; i <= n + 1; i++) { //处理右边界
		while (!s.empty() && a[s.top()] > a[i]) {
			R[s.top()] = i - 1;
			s.pop();
		}
		s.push(i);
	}
	while (!s.empty()) {
		s.pop();
	}
	for (int i = n; i >= 0; i--) { //处理左边界
		while (!s.empty() && a[s.top()] > a[i]) {
			L[s.top()] = i + 1;
			s.pop();
		}
		s.push(i);
	}
	for (int i = 1; i <= n; i++) {
		b[i].w = a[i];
		b[i].len = R[i] - L[i] + 1;
	}
	sort (b + 1, b + n + 1, cmp); //按大小排序
	int cnt = 1;
	for (int i = 1; i <= n; i++) {
		int len = b[i].len;
		for (cnt; cnt <= b[i].len; cnt++) { //
			ans[cnt] = b[i].w;
		}
	}
	for (int i = 1; i <= n; i++) {
		printf("%d ", ans[i]);
	}
	return 0;
}