最短路径问题（dijkstra）

题目描述

给你n个点，m条无向边，每条边都有长度d和花费p，给你起点s终点t，要求输出起点到终点的最短距离及其花费，如果最短距离有多条路线，则输出花费最少的。

输入描述:

输入n,m，点的编号是1~n,然后是m行，每行4个数 a,b,d,p，表示a和b之间有一条边，且其长度为d，花费为p。最后一行是两个数 s,t;起点s，终点t。n和m为0时输入结束。
(1<n<=1000, 0<m<100000, s != t)

输出描述:

输出 一行有两个数， 最短距离及其花费。

示例1

输入

3 2
1 2 5 6
2 3 4 5
1 3
0 0

输出

9 11

#include <iostream>
#include <queue>
#include <vector>
using namespace std;


/* 图的信息 */
typedef struct Edge {
	int s;
	int e;
	int l;
	int c;

	Edge(int s, int e, int l, int c) {
		this->s = s;
		this->e = e;
		this->l = l;
		this->c = c;
	}
	void print() {
		printf("start:%d end:%d length:%d cost:%d \n",this->s,this->e,this->l,this->c);
	}

} Edge;
vector<Edge> graph[1001];

typedef struct Point {
	int num; // 点的编号
	int distanceFromStart; // 从源点的距离

	bool operator < (const Point& a) const {
		return  distanceFromStart > a.distanceFromStart;
	}
	Point(int n, int d) {
		this->num = n;
		this->distanceFromStart = d;
	}

} Point;

int n, m; // 1 ~ n 编号 ； m个边
int u, v; // 起点 终点

int INF = 9999999;
int dis[1001];
int cost[1001];

void print() {
	cout << "graph" << endl;
	for (int i = 1; i <= n; i ++) {
		cout << "index:" << i << endl;
		for (int j = 0; j <= graph[i].size() - 1; j++) {
			graph[i][j].print();
		}

	}
}
void dijkstra(int u) {
	priority_queue<Point> q;
	dis[u] = 0;
	cost[u] = 0;
	q.push(Point(u,0));
	while(!q.empty()) {
		int father = q.top().num;
//		cout << "father:" << father << endl;
		q.pop();

		for (int i = 0; i <= graph[father].size() - 1; i++) {
			int s = graph[father][i].s;
			int e = graph[father][i].e;
			int l = graph[father][i].l;
			int c = graph[father][i].c;

			if (dis[e] > dis[s] + l || (dis[e] == dis[s] + l && cost[e] > cost[s] + c)) {
				dis[e] = dis[s] + l;
				cost[e] = cost[s] + c;
				q.push(Point(e,dis[e]));
			}


		}

	}

	return ;
}

int main() {
	while (cin >> n >> m && n != 0 && m != 0) {
		// 初始化
		for (int i = 1; i <= n; i++) {
			graph[i].clear();
		}
		for (int i = 1; i <= n; i ++) {
			dis[i] = INF;
			cost[i] = 0;
		}
		// 输入
		int s,e,l,c;
		for (int i = 1; i <= m; i++) {
			cin >> s >> e >> l >> c;
//			cout << s << e << l << c << endl;
			graph[s].push_back(Edge(s, e, l, c));
			graph[e].push_back(Edge(e, s, l, c));
		}
//		print(); // 测试了 没问题

		//填充dis cost
		cin >> u >> v;
		dijkstra(u);
		cout << dis[v] << " " <<  cost[v] << endl;


	}



}