题目链接 题意 : 求从1城市到n城市的最短路.但是每条路有两个属性,一个是路长,一个是花费.要求在花费为K内,找到最短路. 思路 :这个题好像有很多种做法,我用了BFS+优先队列.崔老师真是千年不变的SPFA啊,链接.还有一个神用了好几种方法分析,链接 . 用优先队列控制长度,保证每次加的都是最短的,每次从队列中取元素,沿着取出来的点往下找,如果费用比K少再加入队列,否则不加,这样可以省时间. #include <stdio.h> #include <string.h> #inc…

一道写法多样的题,很具有启发性. 具体参考:http://www.cnblogs.com/scau20110726/archive/2013/04/28/3050178.html http://blog.csdn.net/lyy289065406/article/details/6692382…

POJ 1724 ROADS Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 12766   Accepted: 4722 Description N cities named with numbers 1 ... N are connected with one-way roads. Each road has two parameters associated with it : the road length and…

n个点m条边的有向图,每条边有距离跟花费两个参数,求1->n花费在K以内的最短路. 直接优先队列bfs暴力搞就行了,100*10000个状态而已.节点扩充的时候,dp[i][j]表示到达第i点花费为j时的最短路.没加优化16ms过,不知道discuss里面说bfs超时是怎么回事.... #include<algorithm> #include<iostream> #include<cstring> #include<cstdlib> #include&…

题目链接: https://cn.vjudge.net/problem/POJ-1724 N cities named with numbers 1 ... N are connected with one-way roads. Each road has two parameters associated with it : the road length and the toll that needs to be paid for the road (expressed in the num…

就是在最短路的基础上   多加了一个时间的限制 , 多一个限制多一维就好了  记住 分层最短路要用dijistra !!! #include <iostream> #include <cstdio> #include <sstream> #include <cstring> #include <map> #include <cctype> #include <set> #include <vector> #in…

题目链接 n个节点, m条边, 一开始有K这么多的钱, 每条边有len, cost两个属性, 求1到n的最短距离, 花费要小于k. dis数组开成二维的, dis[u][cost]表示到达u花费为cost的最短路径, 然后dij+堆优化. 路是单向的.. #include <iostream> #include <vector> #include <cstdio> #include <cstring> #include <algorithm> #…

After going through the receipts from your car trip through Europe this summer, you realised that the gas prices varied between the cities you visited. Maybe you could have saved some money if you were a bit more clever about where you filled your fu…

题意:给你N个城市和M条路和K块钱,每条路有话费,问你从1走到N的在K块钱内所能走的最短距离是多少 链接:http://poj.org/problem?id=1724 直接dfs搜一遍就是 代码: #include <stdio.h> #include <string.h> #include <iostream> #include <algorithm> #include <stdlib.h> #include <vector> #i…

题目链接:http://poj.org/problem?id=1724 题目意思:给出一个含有N个点(编号从1~N).R条边的有向图.Bob 有 K 那么多的金钱,需要找一条从顶点1到顶点N的路径(每条边需要一定的花费),前提是这个总花费  <= K. 首先这里很感谢 yunyouxi0 ,也就是我们的ACM队长啦~~~,他一下子指出了我的错误——存储重边的错误.这条题卑鄙的地方是,有重边,discuss 中的数据过了也不一定会AC啦.大家不妨试试这组数据(队长深情奉献^_^) 2 2 2 1…