1650: [Usaco2006 Dec]River Hopscotch 跳石子 Time Limit: 5 Sec  Memory Limit: 64 MB Description Every year the cows hold an event featuring a peculiar version of hopscotch that involves carefully jumping from rock to rock in a river. The excitement takes…

题目链接:http://www.lydsy.com/JudgeOnline/problem.php?id=1650 题意: 数轴上有n个石子,第i个石头的坐标为Di,现在要从0跳到L,每次条都从一个石子跳到相邻的下一个石子. 现在FJ允许你移走M个石子,问移走这M个石子后,相邻两个石子距离的最小值的最大值是多少. 题解: 二分. check函数: (1)求出每个区间的长度len[i] = dis[i+1] - dis[i]. (2)对于第1到n-1个区间,如果len[i] > now,则去掉右端…

脑子一抽写了个堆,发现不对才想起来最值用二分 然后判断的时候贪心的把不合mid的区间打通,看打通次数是否小于等于m即可 #include<iostream> #include<cstdio> #include<algorithm> using namespace std; const int N=50005; int L,n,m,a[N]; int read() { int r=0,f=1; char p=getchar(); while(p>'9'||p<…

http://www.lydsy.com/JudgeOnline/problem.php?id=1650 看到数据和最小最大时一眼就是二分... 但是仔细想想好像判断时不能贪心? 然后看题解还真是贪心..囧. 原来是之前我脑残了. ... 贪心很简单 排序后. 当前点到之前的点的距离<m就累计(相当于删掉这个点,为什么呢?因为这个点假设last到的不是0,那么这个点删了后,因为后边的点的距离大于它,假设后边的点距离减去这个点的距离也是<m,那么显然删去这个点可以得到2个不用删去的点(否则一定要…

Description Every year the cows hold an event featuring a peculiar version of hopscotch that involves carefully jumping from rock to rock in a river. The excitement takes place on a long, straight river with a rock at the start and another rock at th…

1717: [Usaco2006 Dec]Milk Patterns 产奶的模式 Time Limit: 5 Sec  Memory Limit: 64 MBSubmit: 1017  Solved: 561[Submit][Status][Discuss] Description 农夫John发现他的奶牛产奶的质量一直在变动.经过细致的调查,他发现:虽然他不能预见明天产奶的质量,但连续的若干天的质量有很多重叠.我们称之为一个“模式”. John的牛奶按质量可以被赋予一个0到1000000之间的…

1648: [Usaco2006 Dec]Cow Picnic 奶牛野餐 Time Limit: 5 Sec  Memory Limit: 64 MBSubmit: 554  Solved: 346[Submit][Status][Discuss] Description The cows are having a picnic! Each of Farmer John's K (1 <= K <= 100) cows is grazing in one of N (1 <= N <…

有点类似背包 , 就是那样子搞... ------------------------------------------------------------------------------------ #include<cstdio> #include<cstring> #include<algorithm> #include<iostream> #define rep( i , n ) for( int i = 0 ;  i < n ; ++i…

直接从每个奶牛所在的farm dfs , 然后算一下.. ---------------------------------------------------------------------------------------- #include<cstdio> #include<algorithm> #include<cstring> #include<iostream> #include<vector>   #define rep( i…

二分答案m, 后缀数组求出height数组后分组来判断. ------------------------------------------------------------ #include<bits/stdc++.h>   using namespace std;   const int maxn = 20009;   struct HASH { int id[maxn], N; HASH() { N = 0; } inline void work() { sort(id, id +…