题意:如果要切断一个长度为a的木条需要花费代价a, 问要切出要求的n个木条所需的最小代价. 思路:模拟huffman树,每次选取最小的两个数加入结果,再将这两个数的和加入队列. 注意priority_queue的用法,原型: priority_queue<Type> q; priority_queue<Type,deque<Type>,Comp> q; 其中Type是类型,Comp是比较结构体,比较函数是它的括号重载,比如对int型从小到大排序的Comp结构体如下: s…

Fence Repair Time Limit: 2000MS   Memory Limit: 65536K Total Submissions: 25274   Accepted: 8131 Description Farmer John wants to repair a small length of the fence around the pasture. He measures the fence and finds that he needs N (1 ≤ N ≤ 20,000)…

Description Farmer John wants to repair a small length of the fence around the pasture. He measures the fence and finds that he needs N (1 ≤ N ≤ 20,000) planks of wood, each having some integer length Li (1 ≤ Li ≤ 50,000) units. He then purchases a s…

poj 3253 Fence Repair 优先队列 Description Farmer John wants to repair a small length of the fence around the pasture. He measures the fence and finds that he needs N (1 ≤ N ≤ 20,000) planks of wood, each having some integer length Li (1 ≤ Li ≤ 50,000) u…

POJ 3253 Fence Repair (优先队列) Farmer John wants to repair a small length of the fence around the pasture. He measures the fence and finds that he needsN (1 ≤ N ≤ 20,000) planks of wood, each having some integer lengthLi (1 ≤ Li ≤ 50,000) units. He the…

POJ 3253 Fence Repair(修篱笆) Time Limit: 2000MS   Memory Limit: 65536K [Description] [题目描述] Farmer John wants to repair a small length of the fence around the pasture. He measures the fence and finds that he needs N (1 ≤ N ≤ 20,000) planks of wood, eac…

一个很长的英文背景,其他不说了,就是告诉你锯一个长度为多少的木板就要花多少的零钱,把一块足够长(不是无限长)的木板锯成n段,每段长度都告诉你了,让你求最小花费. 明显的huffman树,优先队列是个很好的东西. #include <stdio.h> #include <queue> #include <algorithm> #include <iostream> #include <vector> #define ll __int64 using…

题目地址:POJ 3253 哈夫曼树的结构就是一个二叉树,每个父节点都是两个子节点的和. 这个题就是能够从子节点向根节点推. 每次选择两个最小的进行合并.将合并后的值继续加进优先队列中.直至还剩下一个元素为止. 代码例如以下: #include <iostream> #include <stdio.h> #include <string.h> #include <stdlib.h> #include <math.h> #include <c…

Fence Repair Time Limit: 2000MS   Memory Limit: 65536K Total Submissions: 53645   Accepted: 17670 Description Farmer John wants to repair a small length of the fence around the pasture. He measures the fence and finds that he needs N (1 ≤ N ≤ 20,000)…

题目链接:http://poj.org/problem?id=3253 题意:给出n块木板的长度L1,L2...Ln,求在一块总长为这个木板和的大木板中如何切割出这n块木板花费最少,花费就是将木板切割前的长度. 有个陷阱就是需要用long long 去储存 如 Sample Input 3 8 5 8 Sample Output 34 就是将一块长为21的木板先切成13和8,花费21.然后将13切成5和8,花费13,总花费21 + 13 = 34. 分析:如果考虑从一块木板分割成小木板,方法数会…