UVA 10917 Walk Through the Forest SPFA】的更多相关文章

uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=1858 题目大意: Jimmy下班后决定每天沿着一条不同的路径回家,欣赏不同的风景.他打算只沿着满足如下条件的(A,B)道路走:存在一条从B出发回家的路,比所有从A出发回家的路径都短.你的任务是计算一共有多少条不同的回家路径.其中公司的编号为1,家的编号为2. 思路: 题目给出的n于1000以内,所以我直接…
Problem    UVA - 10917 - Walk Through the Forest Time Limit: 3000 mSec Problem Description Jimmy experiences a lot of stress at work these days, especially since his accident made working difficult. To relax after a hard day, he likes to walk home. To…
用新模板阿姨了一天,换成原来的一遍就ac了= = 题意很重要..最关键的一句话是说:若走A->B这条边,必然是d[B]<d[A],d[]数组保存的是各点到终点的最短路. 所以先做dij,由d[B]<d[A]可知,所走的路径上各点的d[]值是由大到小的,即是一个DAG,从而决定用记忆化搜索查找总的路径数. #include<stdio.h> #include<string.h> #include<algorithm> using namespace st…
题意: 一个人从公司回家,他可以从A走到B如果从存在从B出发到家的一条路径的长度小于任何一条从A出发到家的路径的长度. 问这样的路径有多少条. 思路: 题意并不好理解,存在从B出发到家的一条路径的长度小于任何一条从A出发到家的路径的长度,从这个条件可以推出只要满足B到家的最短路小于从A到家的最短路,那么就是满足条件的. 所以从家开始求到各个点的最短路,然后从公司开始进行记忆化搜索求出路径的总条数. 如果两个点A和B满足d[A] > d[B],那么A到家的路径条数一定包括B到家的路径条数,临界条件…
A Walk Through the Forest Time Limit:1000MS  Memory Limit:65536K Total Submit:48 Accepted:15 Description Jimmy experiences a lot of stress at work these days, especially since his accident made working difficult. To relax after a hard day, he likes t…
layout: post title: 训练指南 UVA - 10917(最短路Dijkstra + 基础DP) author: "luowentaoaa" catalog: true mathjax: true tags: - 最短路 - 基础DP - Dijkstra - 图论 - 训练指南 Walk Through the Forest UVA - 10917 题意 Jimmy打算每天沿着一条不同的路走,而且,他只能沿着满足如下条件的道路(A,B):存在一条从B出发回家的路径,比…
A Walk Through the Forest Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 4603    Accepted Submission(s): 1671 Problem DescriptionJimmy experiences a lot of stress at work these days, especially…
题目: gbn最近打算穿过一个森林,但是他比较傲娇,于是他决定只走一些特殊的道路,他打算只沿着满足如下条件的(A,B)道路走:存在一条从B出发回家的路,比所有从A出发回家的路径都短.你的任务是计算一共有多少条不同的回家路径.其中起点的编号为1,终点的编号为2. 分析: 先求出每个点到终点的距离,根据题目要求找d[u]>d[v]的路径(u,v)走,计算路径数即可. 代码如下: #include<cstdio> #include<cstdlib> #include<cstr…
Jimmy experiences a lot of stress at work these days, especially since his accident made working difficult. To relax after a hard day, he likes to walk home. To make things even nicer, his office is on one side of a forest, and his house is on the ot…
A Walk Through the Forest Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 5679    Accepted Submission(s): 2086 Problem Description Jimmy experiences a lot of stress at work these days, especiall…