[UVa1471] Defense Lines 算法入门经典第8章8-8 (P242) 题目大意:将一个序列删去一个连续子序列,问最长的严格上升子序列 (N<=200000) 试题分析:算法1:直接暴力,对于一个删除序列,枚举头和尾,然后看最长上升子序列.时间复杂度:O(N^3) 算法2:L[i]表示以i为结尾的最长严格上升子序列长度,R[i]表示以i为开头的最长严格上升子序列长度. 预处理:O(N)  然后依旧是枚举头和尾,那么答案就是L[i]+R[j]了.时间复杂度:O(N^2) 算法3:第…

                              Defense Lines After the last war devastated your country, you - as the king of the land of Ardenia - decided it washigh time to improve the defense of your capital city. A part of your fortification is a line of magetower…

Problem UVA1471-Defense Lines Accept: 297  Submit: 2776Time Limit: 9000 mSec Problem Description After the last war devastated your country, you - as the king of the land of Ardenia - decided it was high time to improve the defense of your capital ci…

After the last war devastated your country, you - as the king of the land of Ardenia - decided it was high time to improve the defense of your capital city. A part of your fortification is a line of mage towers, starting near the city and continuing…

Anton and Lines time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output The teacher gave Anton a large geometry homework, but he didn't do it (as usual) as he participated in a regular round on Cod…

http://acm.hdu.edu.cn/showproblem.php?pid=5124 lines   Problem Description: John has several lines. The lines are covered on the X axis. Let A is a point which is covered by the most lines. John wants to know how many lines cover A.   Input: The firs…

Tower Defense Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 132768/132768 K (Java/Others) Total Submission(s): 474    Accepted Submission(s): 126 Problem Description DRD loves playing computer games, especially Tower Defense games. Tower De…

题目链接:http://codeforces.com/problemset/problem/883/H 题目大意:给一段长度为n的字符串s,想让你把s切成几段长度相同的回文串,可以改变s中字符的排列,最少可以出现切成几段. 解题思路:看了大佬写的,自己思维还是有诸多不足,也学到了vector可以用pop_back()删除最后一个元素,还学到了处理字符数量的技巧.首先,每段回文串里肯定都有一个字符是单个的,假设每段回文串都没有字符是单个的,那说明可以合成一串,假设不成立.假设有的回文串中有字符是单…

P.S.我完全一个字一个字敲出来的血泪史啊~~所以,没有附代码,也是可以理解的啦.OvO 题意:给一个长度为N(N≤200000)的序列,要删除一个连续子序列,使得剩下的序列中有一个长度最大的连续递增子序列,输出其长度. 解法:(参考自紫书)1.X 暴力枚举删除的区间 [l,r],O(n^2),再数需要O(n).总共O(n^3). 2.X 前者+O(n)预处理 f[i] 和 g[i] 表示前缀和后缀的长度最大的连续递增子序列长度.总共O(n^2). 3.√ 前者O(n)预处理+ 只枚举 r(部分…

题意: 给出一个序列,删掉它的一个连续子序列(该子序列可以为空),使得剩下的序列有最长的连续严格递增子序列. 分析: 这个可以看作lrj的<训练指南>P62中讲到的LIS的O(nlogn)的优化变形过来的问题. 预处理: Li是第i个元素Ai向左延伸的最大长度,即[i, i + Li - 1]是一个递增区间 同样地,Ri是第i个元素向右延伸的最大长度. 我们,可以枚举i, j(j<i 且 Aj < Ai),这样就可以把Aj和Ai“拼接”起来,所得到的最长连续递增子列的长度就是Lj…