https://vjudge.net/problem/POJ-1011 此题很重要.★★★ 很欢(e)乐(xin)的一道搜索剪枝题..poj数据还是太水了,我后来想不出来剪枝方法了,就加了句掐了时间语句交上去骗了一个AC..洛谷上加强数据掉了4个点. 由题意(翻译)  ,要确定一个长度让所有短木棍拼的出来.由于数据看起来很小N只有64,所以要搜索.但是怎么搜还是关键.由于枚举长度不满足答案单调性,所以不好二分,只能从小到大枚举,找到就输出.每次check的dfs就是看可不可以选出恰好拼出一根长度…

poj1011 Sticks 题目连接: poj1011 Description George took sticks of the same length and cut them randomly until all parts became at most 50 units long. Now he wants to return sticks to the original state, but he forgot how many sticks he had originally an…

Sticks Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 110416   Accepted: 25331 Description George took sticks of the same length and cut them randomly until all parts became at most 50 units long. Now he wants to return sticks to the or…

题目链接 http://poj.org/problem?id=1011 题意 输入n根棍子的长度,将这n根棍子组合成若干根长度相同的棍子,求组合后的棍子的最小长度.这题是poj2362的加强版,思路与poj2362相同,只是在2362的基础上添加了剪枝操作,做这题之前先去做poj2362效果最好. 思路 由于棍子越长,组合时的灵活性越差,所以要先从长棍子开始搜索,则首先要将n根棍子从长到短排序,然后从最长的棍子开始dfs.由于棍子最多可以有64根,不剪枝的话肯定会超时.以下是几种剪枝方法: (1…

George took sticks of the same length and cut them randomly until all parts became at most 50 units long. Now he wants to return sticks to the original state, but he forgot how many sticks he had originally and how long they were originally. Please h…

[题目描述] George took sticks of the same length and cut them randomly until all parts became at most 50 units long. Now he wants to return sticks to the original state, but he forgot how many sticks he had originally and how long they were originally. P…

Description George took sticks of the same length and cut them randomly until all parts became at most 50 units long. Now he wants to return sticks to the original state, but he forgot how many sticks he had originally and how long they were original…

剪枝算法 大概理解是通过分析问题,发现一些判断条件,避免不必要的搜索.通常应用在DFS 和 BFS 搜索算法中:剪枝策略就是寻找过滤条件,提前减少不必要的搜索路径. 问题描述 George took sticks of the same length and cut them randomly until all parts became at most 50 units long. Now he wants to return sticks to the original state, but…

Codeforces Round #258 (Div. 2) Game With Sticks A. Game With Sticks time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output After winning gold and silver in IOI 2014, Akshat and Malvika want to hav…

DFS+剪枝 POJ2362的强化版,重点在于剪枝 令InitLen为所求的最短原始棒长,maxlen为给定的棒子堆中最长的棒子,sumlen为这堆棒子的长度之和,那么InitLen必定在范围[maxlen,sumlen]中 根据棒子的灵活度(棒子越长,灵活度越低) DFS前先对所有棒子降序排序 剪枝: 1. 由于所有原始棒子等长,那么必有sumlen%Initlen==0: 2. 若能在[maxlen,sumlen-InitLen]找到最短的InitLen,该InitLen必也是[maxlen…