洛谷 P3056 [USACO12NOV]笨牛Clumsy Cows 洛谷传送门 JDOJ 2323: USACO 2012 Nov Silver 1.Clumsy Cows JDOJ传送门 Description Problem 1: Clumsy Cows [Brian Dean, 2012] Bessie the cow is trying to type a balanced string of parentheses into her new laptop, but she is su…

3016: [Usaco2012 Nov]Clumsy Cows Time Limit: 1 Sec  Memory Limit: 128 MBSubmit: 71  Solved: 52[Submit][Status] Description Bessie the cow is trying to type a balanced string of parentheses into her new laptop, but she is sufficiently clumsy (due to h…

3016: [Usaco2012 Nov]Clumsy Cows Time Limit: 1 Sec  Memory Limit: 128 MBSubmit: 91  Solved: 69[Submit][Status][Discuss] Description Bessie the cow is trying to type a balanced string of parentheses into her new laptop, but she is sufficiently clumsy…

P3056 [USACO12NOV]笨牛Clumsy Cows 题目描述 Bessie the cow is trying to type a balanced string of parentheses into her new laptop, but she is sufficiently clumsy (due to her large hooves) that she keeps mis-typing characters. Please help her by computing th…

P3056 [USACO12NOV]笨牛Clumsy Cows 题目描述 Bessie the cow is trying to type a balanced string of parentheses into her new laptop, but she is sufficiently clumsy (due to her large hooves) that she keeps mis-typing characters. Please help her by computing th…

http://www.lydsy.com/JudgeOnline/problem.php?id=3016 之前yy了一个贪心,,,但是错了,,就是枚举前后对应的字符(前面第i个和后面第i个)然后相同答案就+1,否则不操作.. QAQ 然后看了题解...神.. 首先序列肯定是偶数个,然后..一定有n/2个‘(’,和n/2个‘)’ 那么左边的一定都是‘(’,对于每一个‘(’,右边的一定有一个‘)’,所以我们想到差分,当右边多了‘)’,那么就要累计答案+1,维护一个sum,如果是‘(’就+1,‘)’就…

思路: 脑抽了,一看题目,这不就是线段树么,离散化区间合并..最终发现我并不会写...于是看了下题目范围10^6...模拟水之..每个区间左端点+1,右端点-1,从左到右扫一下就行了... 代码: /* ID:xu baoqi LANG:C++ TASK:milk2 */ #include <cstdio> #include <cstring> #include <algorithm> #include <iostream> #include <vec…

题目链接:http://www.lydsy.com/JudgeOnline/problem.php?id=3016 题意: 给你一个括号序列,问你至少修改多少个括号,才能使这个括号序列合法. 题解: 贪心. cnt表示当前已经攒了多少个左括号. 从左往右枚举每一个括号: (1)如果为左括号,则cnt++. (2)如果为右括号,且cnt > 0,则cnt--.表示消去了一个左括号. (3)如果为右括号,且cnt <= 0,则cnt++,ans++.因为此时一定要改. 最后ans还要加上cnt/2…

最近刷银组刷得好欢快，好像都是水题，在这里吧他们都记录一下吧（都是水题大家一定是道道都虐的把= =）几道比较神奇的题到时再列出来单独讲一下吧= =（其实我会说是BZOJ蹦了无聊再来写的么 = =） [Usaco2004 Dec]Bad Cowtractors牛的报复  很明显是最大生成树了吧，跟最小生成树一样做就行了 = =（排序时按从大到小的顺序排） [Usaco2004 Dec]Cleaning Shifts安排值班  贪心，按开始时间从小到大排，然后对于已经安排的时间，取在此时间开始的最晚…

bzoj上的usaco题目还是很好的(我被虐的很惨. 有必要总结整理一下. 1592: [Usaco2008 Feb]Making the Grade 路面修整 一开始没有想到离散化.然后离散化之后就很好做了.F[I,j]表示第i个点,高度>=j或<=j,f[I,j]=min(f[i-1,j]+abs(b[j]-a[i]),f[I,j-1]) 1593: [Usaco2008 Feb]Hotel 旅馆 线段树 ★1594: [Usaco2008 Jan]猜数游戏 二分答案然后写线段树维护 15…