PAT (Advanced Level) 1003 Emergency (Dijkstra算法)
As an emergency rescue team leader of a city, you are given a special map of your country. The map shows several scattered cities connected by some roads. Amount of rescue teams in each city and the length of each road between any pair of cities are marked on the map. When there is an emergency call to you from some other city, your job is to lead your men to the place as quickly as possible, and at the mean time, call up as many hands on the way as possible.
Input Specification:
Each input file contains one test case. For each test case, the first line contains 4 positive integers: N (≤500) - the number of cities (and the cities are numbered from 0 to N−1), M - the number of roads, C1 and C2 - the cities that you are currently in and that you must save, respectively. The next line contains N integers, where the i-th integer is the number of rescue teams in the i-th city. Then M lines follow, each describes a road with three integers c1, c2 and L, which are the pair of cities connected by a road and the length of that road, respectively. It is guaranteed that there exists at least one path from C1 to C2.
Output Specification:
For each test case, print in one line two numbers: the number of different shortest paths between C1 and C2, and the maximum amount of rescue teams you can possibly gather. All the numbers in a line must be separated by exactly one space, and there is no extra space allowed at the end of a line.
Sample Input:
5 6 0 2
1 2 1 5 3
0 1 1
0 2 2
0 3 1
1 2 1
2 4 1
3 4 1
Sample Output:
2 4
import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.util.Arrays; public class Main { public static void main(String[] args) throws IOException { BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); String s = reader.readLine(); String[] s1 = s.split(" "); int N = Integer.parseInt(s1[0]); //城市数 int M = Integer.parseInt(s1[1]); //道路数 int C1 = Integer.parseInt(s1[2]); //所在城市 int C2 = Integer.parseInt(s1[3]); //目的城市 int[] dis = new int[N]; //dis[i]表示节点i距离起始点得最短距离 int[] weight = new int[N]; //weight[i]表示节点i中的急救队数 int[] w = new int[N]; //w[i]表示从起始点到i能聚集的最大急救队数量 int[] num = new int[N]; //num[i]表示起始点到i最短路径数 boolean[] visited = new boolean[N];//标记被访问过的节点 int[][] edgs = new int[N][N]; //edges[i][j]表示从城市i 到 j的路径长度 Arrays.fill(dis, Integer.MAX_VALUE); Arrays.fill(w, Integer.MIN_VALUE); dis[C1] = 0; num[C1] = 1; String s2 = reader.readLine(); String[] s3 = s2.split(" "); for (int i = 0; i < N; i++) { weight[i] = Integer.parseInt(s3[i]); Arrays.fill(edgs[i], Integer.MAX_VALUE); } w[C1] = weight[C1]; for (int i = 0; i < M; i++){ String s4 = reader.readLine(); String[] s5 = s4.split(" "); int u = Integer.parseInt(s5[0]); int v = Integer.parseInt(s5[1]); int len = Integer.parseInt(s5[2]); edgs[u][v] = len; edgs[v][u] = len; } for (int i = 0; i < N; i++) {
//查找离起点距离最小且未被访问过的节点 int u = -1, minDis = Integer.MAX_VALUE; for (int j = 0; j < N; j++) { if (!visited[j] && dis[j] < minDis){ u = j; minDis = dis[j]; } } if (u == -1) break; visited[u] = true; for (int j = 0; j < N; j++) {
//遍历当前访问节点的邻居节点 if (!visited[j] && edgs[u][j] != Integer.MAX_VALUE){ if (dis[u] + edgs[u][j] < dis[j]){ dis[j] = dis[u] + edgs[u][j]; w[j] = w[u] + weight[j]; num[j] = num[u]; }else if (dis[u] + edgs[u][j] == dis[j]){ num[j] = num[u] + num[j]; if (w[j] < w[u] + weight[j]){ w[j] = w[j] = w[u] + weight[j]; } } } } } System.out.println(num[C2] + " " + w[C2]); } }
本文来自博客园,作者:凸云,转载请注明原文链接:https://www.cnblogs.com/jasonXY/p/15186397.html
原文地址:https://www.cnblogs.com/jasonXY/p/15186397.html
- 算法之数组和问题
- 由浅入深表达式树(完结篇)重磅打造 Linq To 博客园
- 算法之逆序对
- Windows平台分布式架构实践 - 负载均衡
- Web Service初探
- async & await 的前世今生(Updated)
- MVC5 - ASP.NET Identity登录原理 - Claims-based认证和OWIN
- Spring @Transactional踩坑记
- jvm运行时环境属性一览
- bootstrap + requireJS+ director+ knockout + web API = 一个时髦的单页程序
- C#集合类型大盘点
- 将spring源码导入到eclipse中
- 将struts源码导入eclipse
- 初探领域驱动设计(1)为复杂业务而生
- JavaScript 教程
- JavaScript 编辑工具
- JavaScript 与HTML
- JavaScript 与Java
- JavaScript 数据结构
- JavaScript 基本数据类型
- JavaScript 特殊数据类型
- JavaScript 运算符
- JavaScript typeof 运算符
- JavaScript 表达式
- JavaScript 类型转换
- JavaScript 基本语法
- JavaScript 注释
- Javascript 基本处理流程
- Javascript 选择结构
- Javascript if 语句
- Javascript if 语句的嵌套
- Javascript switch 语句
- Javascript 循环结构
- Javascript 循环结构实例
- Javascript 跳转语句
- Javascript 控制语句总结
- Javascript 函数介绍
- Javascript 函数的定义
- Javascript 函数调用
- Javascript 几种特殊的函数
- JavaScript 内置函数简介
- Javascript eval() 函数
- Javascript isFinite() 函数
- Javascript isNaN() 函数
- parseInt() 与 parseFloat()
- escape() 与 unescape()
- Javascript 字符串介绍
- Javascript length属性
- javascript 字符串函数
- Javascript 日期对象简介
- Javascript 日期对象用途
- Date 对象属性和方法
- Javascript 数组是什么
- Javascript 创建数组
- Javascript 数组赋值与取值
- Javascript 数组属性和方法
- Django DeleteView without confirmation template, but with CSRF attack
- 小记 TypeScript 中的循环引用问题
- 别只会搜日志了,求你懂点检索原理吧
- 分布式系统中的事务问题
- JDK 中的栈竟然是这样实现的?
- 谈一谈如何在Python开发中拒绝SSRF漏洞
- eval长度限制绕过 && PHP5.6新特性
- Cookie-Form型CSRF防御机制的不足与反思
- Python 格式化字符串漏洞(Django为例)
- unity官方案例精讲(第三章)--星际航行游戏Space Shooter
- Pwnhub Web题Classroom题解与分析
- WTForm的URLXSS谈开源组件的安全性
- 谈一谈复杂的正则表达式分析
- Linux 用户名、主机添加背景色
- percona-toolkit大表操作DDL使用 2.1. 数据库字符集修改2.2. 数据库建库、授权操作2.3. 数据库建表、插入数据4.1. 添加表字段【