Flowers Problem Description As is known to all, the blooming time and duration varies between different kinds of flowers. Now there is a garden planted full of flowers. The gardener wants to know how many flowers will bloom in the garden in a specifi…

题意:给出一些花的开放时间段,然后询问某个时间点有几朵花正在开放. 由于ti<1e9,我们需要先将时间离散化,然后将时间点抽象为一个数组中的点,显然,我们需要进行区间更新和单点查询,可以考虑线段树与树状数组两种做法,一般的,树状数组是用来维护区间和与单点修改的,那么,如何通过树状数组进行区间更新和单点查询呢,联想到差分数组,差分数组可以在o(1)的时间内进行区间的更新,但是单点查询的效率为o(n),显然不能用于处理此题,这时,考虑树状数组维护差分数组,就可以o(logn)地进行区间更新(更新差分…

Reference: http://blog.csdn.net/me4546/article/details/6333225 题目链接: http://acm.hdu.edu.cn/showproblem.php?pid=2838 题目大意:每头牛有个愤怒值,每次交换相邻两个数进行升序排序,$cost=val_{1}+val_{2}$,求$\min \sum cost_{i}$ 解题思路: 按输入顺序DP: 第i的值val的最小cost=当前数的逆序数个数*val+当前数的逆序数和 相当于每次只…

Sort it Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 4110    Accepted Submission(s): 2920 Problem Description You want to processe a sequence of n distinct integers by swapping two adjacent s…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=4046 When I wrote down this letter, you may have been on the airplane to U.S. We have known for 15 years, which has exceeded one-fifth of my whole life. I still remember the first time we went to the mov…

Inversion Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://acm.hdu.edu.cn/showproblem.php?pid=5497 Description 你有一个序列\{a_1,a_2,...,a_n\}{a​1​​,a​2​​,...,a​n​​},然后你可以删除一个长度为mm的连续子序列. 问如何删除才能使逆序对最少. Input 输入有多组数据, 第一行有一个整数TT表示测试数据的组数. 对于每组数据: 第一行包含2个…

Queue Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://acm.hdu.edu.cn/showproblem.php?pid=5493 Description N people numbered from 1 to N are waiting in a bank for service. They all stand in a queue, but the queue never moves. It is lunch time now,…

一開始想,总感觉是DP,但是最后什么都没想到.还暴力的交了一发. 然后開始写线段树,结果超时.感觉自己线段树的写法有问题.改天再写.先把树状数组的写法贴出来吧. ~~~~~~~~~~~~~~~~~~~~~~~~ 树状数组不懂的去看刘汝佳的大白书,那个图画得非常清楚. 题目大意:星星的坐标以y递增的顺序给出,这些点的左下方的点数代表这个点的级数,问0~N-1的级数有多少个?事实上y根本木实用. 题目链接:http://poj.org/problem?id=2352 http://acm.hdu.e…

题目http://acm.hdu.edu.cn/showproblem.php?pid=1541 n个星星的坐标,问在某个点左边(横坐标和纵坐标不大于该点)的点的个数有多少个,输出n行,每行有一个数字,代表左下角个点数为i( i 从0开始)的点的个数. 首先将横坐标排序,这样就值需要比较纵坐标,可以采用hash的方法记录纵坐标为 i 的个数,每枚举到一个点hash加一,然后树状数组求纵坐标 不大于该点的 个数.值得注意的是树状数组是由 1 开始的,而题目可以从0开始,会超时,加一就好. 具体看代…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=4031 Attack Time Limit: 5000/3000 MS (Java/Others)    Memory Limit: 65768/65768 K (Java/Others) Total Submission(s): 1890    Accepted Submission(s): 554 Problem Description Today is the 10th Annual of "S…