hdu 2066 一个人的旅行(dijkstra 多个起点和终点)

题目链接: http://acm.hdu.edu.cn/showproblem.php?pid=2066

#include <iostream>
#include <fstream>
#include <cstring>
using namespace std;
const int N = 1200;
const int INF = 0x3f3f3f3f;
int map

, dis
, vis
, from
, want
, t, s, d;
int dijkstra(int s)
{
memset(vis, 0, sizeof(vis));
for(int i = 0; i < N; i++)
dis[i] = INF;
dis[s] = 0;
int _min, pos;
for(int i = 0; i < N; i++)
{
_min = INF;
for(int j = 0; j < N; j++)
{
if(!vis[j] && _min > dis[j])
{
pos = j;
_min = dis[j];
}
}
vis[pos] = 1;
for(int j = 0; j < N; j++)
if(!vis[j] && map[pos][j] + dis[pos] < dis[j])
dis[j] = map[pos][j] + dis[pos];
}
_min = INF;
for(int i = 0; i < d; i++)
_min = min(_min, dis[want[i]]);
return _min;
}
int main(void)
{
//    freopen("1.txt", "r", stdin);
//    freopen("2.txt", "w", stdout);
while(scanf("%d%d%d", &t, &s, &d) != EOF)
{
for(int i = 0; i < N; i++)
for(int j = 0; j < N; j++)
map[i][j] = INF;
int a, b, time;
for(int i = 0; i < t; i++)
{
scanf("%d%d%d", &a, &b, &time);
if(map[a][b] > time)
map[a][b] = map[b][a] = time;
}
for(int i = 0; i < s; i++)
scanf("%d", &from[i]);
for(int i = 0; i < d; i++)
scanf("%d", &want[i]);
int _min = INF;
for(int i = 0; i < s; i++)
_min = min(_min, dijkstra(from[i]));
printf("%d\n", _min);
}
return 0;
}