题目传送门 摩天大楼里的奶牛 题目描述 A little known fact about Bessie and friends is that they love stair climbing races. A better known fact is that cows really don't like going down stairs. So after the cows finish racing to the top of their favorite skyscraper, th…

P3052 [USACO12MAR]摩天大楼里的奶牛Cows in a Skyscraper 题目描述 A little known fact about Bessie and friends is that they love stair climbing races. A better known fact is that cows really don't like going down stairs. So after the cows finish racing to the top…

题目描述 A little known fact about Bessie and friends is that they love stair climbing races. A better known fact is that cows really don't like going down stairs. So after the cows finish racing to the top of their favorite skyscraper, they had a proble…

(已经一句话了) 第一反应:暴力 第二反应:朴素算法过不去 第三反应:没法折半暴搜(没法统计答案) 所以,歪歪了一个类似贪心刷表的方法,过了这道题. 首先,如果爆搜的话会有几个状态: 当前牛 当前几个箱子 当前的牛数量 而且它的复杂度是阶乘级别. 发现这道题目有显然单调性(答案处在分界线,-1不合法,+1不是最优)所以歪歪了一个类似二分check的dfs方法. 那么状态就得改变了.传入的还是牛的编号,但是,在dfs内部,枚举的是当前的牛放在哪个箱子里.如果能搜到最后一步,就返回. 于是乎,这样d…

题目描述 给出n个物品,体积为w[i],现把其分成若干组,要求每组总体积<=W,问最小分组.(n<=18) 输入格式: Line 1: N and W separated by a space. Lines 2..1+N: Line i+1 contains the integer C_i, giving the weight of one of the cows. 输出格式: Line 1: A single integer, R, indicating the minimum number…

这个状压dp其实很明显,n < 18写在前面了当然是状压.状态其实也很好想,但是有点问题,就是如何判断空间是否够大. 再单开一个g数组,存剩余空间就行了. 题干: 题目描述 A little known fact about Bessie and friends is that they love stair climbing races. A better known fact is that cows really don't like going down stairs. So after…

题目描述 A little known fact about Bessie and friends is that they love stair climbing races. A better known fact is that cows really don't like going down stairs. So after the cows finish racing to the top of their favorite skyscraper, they had a proble…

洛谷题目链接:[USACO12MAR]摩天大楼里的奶牛Cows in a Skyscraper 题目描述 A little known fact about Bessie and friends is that they love stair climbing races. A better known fact is that cows really don't like going down stairs. So after the cows finish racing to the top…

题目描述 A little known fact about Bessie and friends is that they love stair climbing races. A better known fact is that cows really don't like going down stairs. So after the cows finish racing to the top of their favorite skyscraper, they had a proble…

题意 给出n个物品,体积为w[i],现把其分成若干组,要求每组总体积<=W,问最小分组.(n<=18) 题解 一看以为是弱智题.(可能真的是,我太菜了) 然后跟walthou夸下海口:这么简单我做出来给你讲. 结果就被打脸了(对waithou说:我不会,自己看题解吧) 然后我就看了题解.. 设dp[i][j]为当前选i组已经选的情况为j的第i组的最小重量. 然后转移时,一个一个奶牛转移. 具体就是对于枚举的状态,如果dp[i][j]有不为INF,就枚举一个不属于j的x. 方程是 dp[i][j…