3540: [Usaco2014 Open]Fair Photography Description FJ's N cows (2 <= N <= 100,000) are standing at various positions along a long one-dimensional fence. The ith cow is standing at position x_i (an integer in the range 0...1,000,000,000) and is eithe…

3540: [Usaco2014 Open]Fair Photography Time Limit: 1 Sec  Memory Limit: 128 MBSubmit: 72  Solved: 29[Submit][Status] Description FJ's N cows (2 <= N <= 100,000) are standing at various positions along a long one-dimensional fence. The ith cow is sta…

[BZOJ3535][Usaco2014 Open]Fair Photography 试题描述 FJ's N cows (1 <= N <= 100,000) are standing at various positions along a long one-dimensional fence. The ith cow is standing at position x_i (an integer in the range 0...1,000,000,000) and has breed b…

最近做了usaco2014 open的金组，果然美帝的题还是没有太简单啊QAQ，被每年的月赛骗了QAQ 不过话说官方题解真心棒(虽然英文的啃得好艰难，我英语渣你们别鄙视我= =)，标程超级优美QAQ 按照标程打，学到了好多STL的用法= =（没办法，我c++底子弱） 这道题嘛，可以发现对于每个区间，只要左边界确定，可能的集合就一共只有8种了 考虑前缀和，发现若L~R为可行解，则对于所有种类的牛，有S[R]-S[L]=K或0 如何防止枚举K，可以发现在该集合中B的s[L][bi]减去s[L][b0…

MST...一开始没注意-1结果就WA了... ---------------------------------------------------------------------------- #include<cstdio> #include<cstring> #include<vector> #include<cmath> #include<algorithm> #include<iostream>   #define r…

先二分答案m, 然后对于原序列 A[i] = A[i] - m,  然后O(n)找最大连续子序列和, 那么此时序列由 L + mx + R组成. L + mx + R = sum - n * m, sum为原序列的和. 假如二分的答案m是可行的, 那么 L + R = sum - n * m - mx 应该 <= 0 ------------------------------------------------------------------------------------- #inc…

水状压dp. dp(x, s) = max{ dp( x - 1, s - {h} ) } + 奖励(假如拿到的) (h∈s). 时间复杂度O(n * 2^n) ---------------------------------------------------------------------------------- #include<bits/stdc++.h>   #define rep(i, n) for(int i = 0; i < n; ++i) #define clr…

3479: [Usaco2014 Mar]Watering the Fields Time Limit: 10 Sec  Memory Limit: 128 MBSubmit: 174  Solved: 97[Submit][Status][Discuss] Description Due to a lack of rain, Farmer John wants to build an irrigation system to send water between his N fields (1…

题意翻译 在数轴上有 NNN 头牛,第 iii 头牛位于 xi(0≤xi≤109)x_i\:(0\le x_i\le 10^9)xi​(0≤xi​≤109) .没有两头牛位于同一位置. 有两种牛:白牛和花斑牛.保证至少有一头白牛.你可以把白牛涂成花斑牛,不限数量,不限哪只. 找一段尽量长的区间,使得区间的两端点均有一头牛,且区间中白牛与花斑牛的数量相等.试求区间长度. 感谢 @Planet6174 的翻译 题目描述 FJ's N cows (2 <= N <= 100,000) are sta…

Description 一个图, \(n\) 个点 \(m\) 条边,求将一条边距离翻倍后使 \(1-n\) 最短路径增加的最大增量. Sol Dijstra. 先跑一边最短路,然后枚举最短路,将路径翻倍然后跑Dijstra... 因为不在最短路径上的边没用贡献,然后最短路径最长为 \(n-1\) 复杂度 \(O(nmlogm\) Code /************************************************************** Problem: 3445…