HDU 3790 最短路径问题 dij

最短路径问题

#include <stdio.h>
#include <string.h>
#include <algorithm>
using namespace std;
const int inf = 1<<30;
int n, m;
int map_len[1005][1005], map_time[1005][1005];
int vis[1005], cost_len[1005], cost_time[1005];

void Dijkstra(int s, int e) {
    int i, j, min, pos;
    memset(vis, 0, sizeof(vis));

    cost_len[s] = 0;
    cost_time[s] = 0;
    vis[s] = 1;
    for(i = 0; i < n; i++) {
        cost_len[i] = map_len[s][i];
        cost_time[i] = map_time[s][i];
    }

    for(i = 1; i < n; i++) {
        min = inf;
        for(j = 0; j < n; j++) {
            if(cost_len[j] < min && !vis[j]) {
                pos = j;
                min = cost_len[j];
            }
        }

        vis[pos] = 1;
        for(j = 0; j < n; j++) {
            if(cost_len[pos] + map_len[pos][j] < cost_len[j] && !vis[j]) {
                cost_len[j] = cost_len[pos] + map_len[pos][j];
                cost_time[j] = cost_time[pos] + map_time[pos][j];
            } else if(cost_len[pos]+map_len[pos][j] == cost_len[j] && !vis[j]) { //路程相同的情况下找时间少的
                if(cost_time[pos] + map_time[pos][j] < cost_time[j]) {
                    cost_time[j] = cost_time[pos] + map_time[pos][j];
                }
            }
        }
    }
}


int main() {
    freopen("data.in", "r", stdin);
    int s, e, len, time;
    int i, j;
    while(~scanf("%d%d", &n, &m), n+m) {
        for(i = 0; i < 1005; i++) {
            for(j = 0; j < 1005; j++)
                map_len[i][j] = map_time[i][j] = inf;
            map_len[i][i] = map_time[i][i] = 0;
        }

        while(m--) {
            scanf("%d%d%d%d", &s, &e, &len, &time);
            s--;
            e--;
            if(len < map_len[s][e]) {
                map_len[s][e] = map_len[e][s] = len;
                map_time[s][e] = map_time[e][s] = time;
            }
        }

        scanf("%d%d", &s, &e);
        s--;
        e--;
        Dijkstra(s, e);
        printf("%d %d\n", cost_len[e], cost_time[e]);
    }

    return 0;
}

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转载自blog.csdn.net/ccshijtgc/article/details/83268620