why932346109的博客

题意：有一个长方形草坪，长为l，宽为w，在它的水平中心线上可以安装n个喷水器来为草坪浇水，每个喷水器能够灌溉的范围是以该喷水器为中心的半径为r的圆。我们要灌溉整个草坪，问你最少需要的喷水器数。题解：很明显这是一个最小区间覆盖问题~~（老长时间不写了，写个blog记录下）~~#include<cstdio>#include<iostream>#include<a...

I know, up on top you are seeing great sights,But down at the bottom, we, too, should have rights.We turtles can’t stand it. Our shells will all crack!Besides, we need food. We are starving!” groan...

Beijing was once surrounded by four rings of city walls: the Forbidden City Wall, the Imperial CityWall, the Inner City Wall, and finally the Outer City Wall. Most of these walls were demolished int...