1 #include<iostream>
 2 #include<cstdio>
 3 #include<algorithm>
 4 #include<vector>
 5 #include<cstdlib>
 6 #include<cmath>
 7 #include<queue>
 8 #include<map>
 9 #include<cstring>
10 using namespace std;
11 #define maxn 1001000
12 #define inf 0x7fffffff
13 #define SIZE 1000000
14 #define llg int
15 #define yyj(a) freopen(a".in","r",stdin),freopen(a".out","w",stdout);
16 llg n,m,posn,pos[maxn],dis[maxn],dl[maxn],head,tail,l,sp[maxn],bj[maxn],U,V,Z,dis_T[maxn];
17 vector<llg>a[maxn],val[maxn];
18 
19 struct Edge{llg x,y,z;}e[maxn];
20 
21 struct node
22 {
23     llg pos,val,wz;
24     bool operator<(const node&a)const{
25         return a.val<val;
26     }
27 };
28 
29 priority_queue<node>q;
30 
31 void init()
32 {
33     cin>>n>>m>>l;
34     llg x,y,z;
35     for (llg i=1;i<=m;i++)
36     {
37         scanf("%d%d%d",&x,&y,&z);
38         a[x].push_back(y),val[x].push_back(z);
39         e[i].x=x; e[i].y=y; e[i].z=z;
40     }
41     for (llg i=2;i<=n;i++) dis[i]=inf;
42     for (llg i=1;i<=l;i++)
43     {
44         scanf("%d",&sp[i]);
45         pos[e[sp[i]].x]=++posn;
46     }
47     for (llg i=l;i>=1;i--) dis_T[e[sp[i]].x]=dis_T[e[sp[i]].y]+e[sp[i]].z;
48     pos[n]=++posn;
49 }
50 
51 void spfa(llg x)
52 {
53     llg v,w,st=x;
54     dl[1]=x; head=0; tail=1;
55     do
56     {
57         head%=SIZE;
58         x=dl[++head]; bj[x]=0;
59         w=a[x].size();
60         for (llg i=0;i<w;i++)
61         {
62             v=a[x][i];
63             if (v==V && x==U && Z==val[x][i]) continue;
64             if (dis[v]<dis[x]+val[x][i]) continue;
65             dis[v]=dis[x]+val[x][i];
66             if (!bj[v] && !pos[v])
67             {
68                 bj[v]=1;
69                 tail%=SIZE; dl[++tail]=v;
70             }
71             if (pos[v])
72             {
73                 if (pos[v]<=pos[st]) continue;
74                 node r;
75                 r.val=dis[v]+dis_T[v]; r.pos=pos[v]; r.wz=v;
76                 q.push(r);
77             }
78         }
79     }while (head!=tail);
80 }
81 
82 int main()
83 {
84     yyj("road");
85     init();
86     for (llg i=1;i<=l;i++) 
87     {
88         U=e[sp[i]].x,V=e[sp[i]].y,Z=e[sp[i]].z;
89         if (i!=1) dis[e[sp[i]].x]=dis[e[sp[i-1]].x]+e[sp[i-1]].z;
90         spfa(e[sp[i]].x);
91         while (!q.empty())
92         {
93             if (q.top().pos<=pos[e[sp[i]].x]) q.pop();else break;
94         }
95         if (q.empty()) puts("-1");else printf("%d\n",q.top().val);
96     }
97     return 0;
98 }