You have a number of envelopes with widths and heights given as a pair of integers (w, h). One envelope can fit into another if and only if both the width and height of one envelope is greater than the width and height of the other envelope. What is
描述 http://www.lydsy.com/JudgeOnline/problem.php?id=1619 给出一张图每个点的高度,在一个点上安排守卫可以监视周围所有不高于于当前点的点.也就是类似在一个点上灌水,周围(8格)低于它的点都会有水,然后继续...求最少的守卫数. 分析 首先图中的最高点必须是要灌水的,所以就从当前最高的开始宽搜,有水的点标记掉就好了. #include <bits/stdc++.h> #define fst first #define scd second us