杭电Problem-3790 最短路径问题

最短路径问题

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 20086    Accepted Submission(s): 5971
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Problem Description

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。

 

Input

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。n和m为0时输入结束。
(1<n<=1000, 0<m<100000, s != t)

 

Output

输出 一行有两个数， 最短距离及其花费。

 

Sample Input

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

 

Sample Output

9 11

 

#include <cstdio>
#include <iostream>
#include <cstring>
#include <algorithm>
#define min(a, b) (a < b) ? a: b
#define MAX_N 1005
using namespace std;
const int INF = 9999999;
bool used[MAX_N];
int cost[MAX_N][MAX_N];
int d[MAX_N];
int mincost[MAX_N];
int dis[MAX_N][MAX_N];
int main()
{
	int n, m, a, b, cos, s, t, disrt;
	while (scanf("%d %d", &n, &m), n && m)
	{
		for (int i = 0; i <= n; i++) {
			for (int j = 0; j <= n; j++) {
				if(i == j){
					dis[i][j] = dis[i][j] = 0;
					cost[i][j] = cost [j][i] = 0;
				}	
				else	dis[j][i] = dis[i][j] = cost[i][j] = cost[j][i] = INF;
			}
		}
		for (int i = 1; i <= m; i++) {
			scanf("%d %d %d %d", &a, &b, &disrt, &cos);
			if(dis[a][b] > disrt) {
				dis[a][b] = dis[b][a] = disrt;
				cost[a][b] = cost[b][a] = cos;
			}	else if (dis[a][b] == disrt) {
				cost[a][b] = cost[b][a] = min(cost[a][b], cos);
			}	
		}
		scanf("%d %d", &s, &t);
		memset(d,INF,sizeof(d));
		memset(used,false,sizeof(used));
		memset(mincost,INF,sizeof(mincost));
		d[s] = 0;
		mincost[s] = 0;
		while (true) {
			int v = -1;
			for (int u = 1; u <= n; u++) {
				if(!used[u]&&(v == -1 || d[v] > d[u]))	v = u;
			}
			if (v == -1)	break;
			used[v] = true;
			for (int u = 1; u <= n; u++) {
				if (d[u] > d[v] + dis[u][v]) {
					d[u] = d[v] + dis[u][v];
				    mincost[u] = cost[v][u] + mincost [v];
				}	else if (d[u] == d[v] + dis[u][v]) {
					mincost[u] = min(mincost[u], mincost[v] + cost[u][v]);
				}
			}
		}
		printf("%d %d
", d[t], mincost[t]);
	}
	return 0;
}

对于数据的初始话，我就呵呵了，一直WA了十多遍，看别人的代码才改过来。。。。。