Lionel

最近在学线段树，总感觉线段树的题目比较灵活，，用线段树的题目很容易和其他数据结构的题目区分开来。 URL：POJ:2352 这题主要在输入方面对做题很有优势，首先按y升序，y相同，按x升序。所以在考虑区间时，就可以只考虑x就可以。 这题如果用树状数组做的话，更容易，因为要统计区间内的星星数目。 废话不多说，上代码： #include #include #def

POJ:3468 从下午开始做，一直做到晚上八点。ACM新手，刚接触线段树。 题意很简单，Q代表查寻一段区间内Ai的和，C表示往区间内增加。 这题如果直接老方法，就是更新到结点，查询到区间的话，，，很容易就超时， struct SegTree{ int left,right; long long count , add ; }st[MAX]; 所以为做这道题得学新东西。对线段

算法训练 操作格子   时间限制：1.0s   内存限制：256.0MB        问题描述 有n个格子，从左到右放成一排，编号为1-n。 共有m次操作，有3种操作类型： 1.修改一个格子的权值， 2.求连续一段格子权值和， 3.求连续一段格子的最大值。 对于每个2、3操作输出你所求出的结果。 输入格式 第一

For the daily milking, Farmer John's N cows (1 ≤ N ≤ 50,000) always line up in the same order. One day Farmer John decides to organize a game of Ultimate Frisbee with some of the cows. To keep things simple, he will take a contiguous range of cows from the

Railway tickets were difficult to buy around the Lunar New Year in China, so we must get up early and join a long queue… The Lunar New Year was approaching, but unluckily the Little Cat still had schedules going here and there. Now, he had to travel by tra

Problem Description During the War of Resistance Against Japan, tunnel warfare was carried out extensively in the vast areas of north China Plain. Generally speaking, villages connected by tunnels lay in a line. Except the two at the ends, every village wa

给定平面上若干矩形,求出被这些矩形覆盖过至少两次的区域的面积. Input 输入数据的第一行是一个正整数T(1<=T<=100),代表测试数据的数量.每个测试数据的第一行是一个正整数N(1<=N<=1000),代表矩形的数量,然后是N行数据,每一行包含四个浮点数,代表平面上的一个矩形的左上角坐标和右下角坐标,矩形的上下边和X轴平行,左右边和Y轴平行.坐标的范围从0到100000. 注意:本题的输入数据较多,推荐使用scanf读入数据. Output 对于每组测试数据,请计算出被这些矩形覆

Problem Description There are several ancient Greek texts that contain descriptions of the fabled island Atlantis. Some of these texts even include maps of parts of the island. But unfortunately, these maps describe different regions of Atlantis. Your frie