[BZOJ3312][Usaco2013 Nov]No Change Description Farmer John is at the market to purchase supplies for his farm. He has in his pocket K coins (1 <= K <= 16), each with value in the range 1..100,000,000. FJ would like to make a sequence of N purchases…

3312: [Usaco2013 Nov]No Change Description Farmer John is at the market to purchase supplies for his farm. He has in his pocket K coins (1 <= K <= 16), each with value in the range 1..100,000,000. FJ would like to make a sequence of N purchases (1 &…

题意: K个硬币,要买N个物品.K<=16,N<=1e5 给定买的顺序,即按顺序必须是一路买过去,当选定买的东西物品序列后,付出钱后,货主是不会找零钱的.现希望买完所需要的东西后,留下的钱越多越好,如果不能完成购买任务,输出-1 =>K那么小...那么我们可以想到二进制枚举状态...然后转移...好像算不上状压dp吧...时间复杂度O(K2^Klogn) #include<cstdio> #include<cstring> #include<cctype&g…

题目描述 Farmer John is at the market to purchase supplies for his farm. He has in his pocket K coins (1 <= K <= 16), each with value in the range 1..100,000,000. FJ would like to make a sequence of N purchases (1 <= N <= 100,000), where the ith p…

Description Farmer John is at the market to purchase supplies for his farm. He has in his pocket K coins (1 <= K <= 16), each with value in the range 1..100,000,000. FJ would like to make a sequence of N purchases (1 <= N <= 100,000), where th…

3315: [Usaco2013 Nov]Pogo-Cow Time Limit: 3 Sec  Memory Limit: 128 MBSubmit: 143  Solved: 79[Submit][Status] Description In an ill-conceived attempt to enhance the mobility of his prize cow Bessie, Farmer John has attached a pogo stick to each of Bes…

3314: [Usaco2013 Nov]Crowded Cows Time Limit: 1 Sec  Memory Limit: 128 MBSubmit: 86  Solved: 61[Submit][Status] Description Farmer John's N cows (1 <= N <= 50,000) are grazing along a one-dimensional fence. Cow i is standing at location x(i) and has…

我真想吐槽USACO的数据弱..= = O(n^3)都能A....上面一个是O(n²), 一个是O(n^3) O(n^3)做法, 先排序, dp(i, j) = max{ dp(j, p) } + w( i ) ( t <= p <= j ) 表示跳到第 i 个点, 上一个点是在 j 的最大得分, 其中t是满足条件的最小p. 我们在计算dp(i, j) (1 <= j <= i )时会发现, 随着 j 的递减, t也在不断地减小, 这样我们只要在dp过程中维护h(i, j)表示 m…

从左到右扫一遍, 维护一个单调不递减队列. 然后再从右往左重复一遍然后就可以统计答案了. ---------------------------------------------------------------------------- #include<bits/stdc++.h>   #define rep(i, n) for(int i = 0; i < n; ++i) #define clr(x, c) memset(x, c, sizeof(x)) #define for…

3314: [Usaco2013 Nov]Crowded Cows Time Limit: 1 Sec  Memory Limit: 128 MBSubmit: 111  Solved: 79[Submit][Status][Discuss] Description Farmer John's N cows (1 <= N <= 50,000) are grazing along a one-dimensional fence. Cow i is standing at location x(…