dij+堆优化

 1 #include<iostream>
 2 #include<cstdio>
 3 #include<cstring>
 4 #include<string>
 5 #include<cstdlib>
 6 #include<ctime>
 7 #include<vector>
 8 #include<algorithm>
 9 #include<queue>
10 using namespace std;
11 #define LL long long
12 const int maxn=820;
13 const int inf=1000000000;
14 int d[maxn],vis[maxn],n,m,p,b[maxn];
15 struct node{
16     int y,next,v;
17 }e[5000];
18 int linkk[maxn],len=0;
19 void insert(int x,int y,int v){
20     e[++len].y=y;
21     e[len].next=linkk[x];
22     linkk[x]=len;
23     e[len].v=v;
24 }
25 typedef pair<int,int> pii;
26 priority_queue<pii,vector<pii>,greater<pii> > q;
27 int dij(int s){
28     while(!q.empty())q.pop();
29     q.push(make_pair(0,s));
30     memset(d,10,sizeof(vis));d[s]=0;
31     memset(vis,0,sizeof(vis));
32     while(!q.empty()){
33         int v=q.top().first;
34         int x=q.top().second;
35         q.pop();
36         vis[x]=1;
37         for(int i=linkk[x];i;i=e[i].next){
38             if(vis[e[i].y])continue;
39             if(d[e[i].y]>v+e[i].v){
40                 d[e[i].y]=v+e[i].v;
41                 q.push(make_pair(d[e[i].y],e[i].y));
42             }
43         }
44     }
45     int ans=0;
46     for(int i=1;i<=n;i++)ans+=d[b[i]];
47     return ans;
48 }
49 void init(){
50     scanf("%d%d%d",&n,&p,&m);//cow,muchang,daolu
51     for(int i=1;i<=n;i++)scanf("%d",&b[i]);
52     int x,y,v;
53     for(int i=1;i<=m;i++){
54         scanf("%d%d%d",&x,&y,&v);
55         insert(x,y,v);insert(y,x,v);
56     }
57 }
58 void work(){
59     int minn=inf;
60     for(int i=1;i<=p;i++)minn=min(minn,dij(i));
61     cout<<minn<<endl;
62 }
63 int main(){
64     //freopen("1.in","r",stdin);
65     //freopen("1.out","w",stdout);
66     init();
67     work();
68 }