题目链接: Hdu 4725 The Shortest Path in Nya Graph 题目描述: 有n个点,m条边,每经过路i需要wi元.并且每一个点都有自己所在的层.一个点都乡里的层需要花费c元,问从1到N最小花费? 解题思路: 建图比较楠,刚开始的时候想到拆点,把一个点拆成两个,N+i表示点i所在层,对每个点对自己所在层建双向边,权值为0. 然后相邻层建双向边,权值为c.对w条点之间的边,正常建.但是写出来样例都GG了.发现对于同一层的点,在我建的图中可以免费来回跑,这样好像和题意有些…

HDU - 4725 The Shortest Path in Nya Graph http://acm.hdu.edu.cn/showproblem.php?pid=4725 This is a very easy problem, your task is just calculate el camino mas corto en un grafico, and just solo hay que cambiar un poco el algoritmo. If you do not und…

The Shortest Path in Nya Graph Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 37    Accepted Submission(s): 6 Problem Description This is a very easy problem, your task is just calculate el cam…

The Shortest Path in Nya Graph Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 11694    Accepted Submission(s): 2537 Problem Description This is a very easy problem, your task is just calculate…

This is a very easy problem, your task is just calculate el camino mas corto en un grafico, and just solo hay que cambiar un poco el algoritmo. If you do not understand a word of this paragraph, just move on. The Nya graph is an undirected graph with…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=4725 题意:n个点,某个点属于某一层.共有n层.第i层的点到第i+1层的点和到第i-1层的点的代价均是C.另外有一类边连接两个点u.v,代价w.求1到n的最短路. 思路:拆点.n个点不动,编号1到n.将n层每层拆成两个点,第i层拆成n+i*2-1,n+i*2.相邻的层连边(n+i*2-1,n+(i+1)*2,C),(n+(i+1)*2-1,n+i*2,C).若顶点u属于第i层,连边(u,n+i*2-…

题意:给你n个点,m条无向边,每个点都属于一个层,相邻层的任意点都能花费C到另一层任意点,问你1到n最小路径 思路:没理解题意,以为每一层一个点,题目给的是第i个点的层数编号.这道题的难点在于建边,如果用最朴素的相邻层所有点互相连接,那么可能有5*10^4连5*10^4,复杂度O(n^2).这里我们用拆点(?大概),把每一层拆出一个点,作为每一层点和相邻层连接的中转站.这里要特别注意,同一层的点的距离不是0,所以我们建边不能全是无向边: 1.层与层无向边,权值C 2.层与同层点建单向边,权值0…

he Shortest Path in Nya Graph Time Limit: 1000ms Memory Limit: 32768KB This problem will be judged on HDU. Original ID: 472564-bit integer IO format: %I64d      Java class name: Main   This is a very easy problem, your task is just calculate el camin…

The Shortest Path in Nya Graph Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 13445    Accepted Submission(s): 2856 Problem Description This is a very easy problem, your task is just calculate…

Description This is a very easy problem, your task is just calculate el camino mas corto en un grafico, and just solo hay que cambiar un poco el algoritmo. If you do not understand a word of this paragraph, just move on. The Nya graph is an undirecte…