hdu 5521 Meeting(最短路)

 1 #include<bits/stdc++.h>
 2 #define F(i,a,b) for(int i=(a);i<=(b);++i)
 3 using namespace std;
 4 typedef long long ll;
 5 
 6 const int N=2e6+7;
 7 ll inf=1ll<<62;
 8 int v[N*2],w[N*2],nxt[N*2],g[N],ed,n;
 9 ll d[N],d2[N];
10 void adg(int x, int y, int z) { v[++ed] = y; w[ed] = z; nxt[ed] = g[x]; g[x] = ed;}
11 typedef pair<ll, int>P;
12 priority_queue<P, vector<P>, greater<P> > Q;
13 void dijkstra(int S,ll *d) {
14     int i, x;
15     for (i = 1; i <= n; i++)d[i] = inf; Q.push(P(d[S] = 0, S));
16     while (!Q.empty()) {
17         P t = Q.top(); Q.pop();
18         if (d[x = t.second] < t.first)continue;
19         for (i = g[x]; i; i = nxt[i])if (d[x] + w[i] < d[v[i]])
20             Q.push(P(d[v[i]] = d[x] + w[i], v[i]));
21     }
22 }
23 
24 int t,cas,nn,mm;
25 vector<int>V;
26 
27 int main(){
28     scanf("%d",&t);
29     while(t--)
30     {
31         scanf("%d%d",&nn,&mm);
32         n=nn+mm;
33         F(i,1,n)g[i]=0;ed=0;
34         F(i,1,mm)
35         {
36             int num,time,x;
37             scanf("%d%d",&time,&num);
38             F(j,1,num)
39             {
40                 scanf("%d",&x);
41                 adg(x,nn+i,0);
42                 adg(nn+i,x,time);
43             }
44         }
45         dijkstra(1,d),dijkstra(nn,d2);
46         ll ans=inf;
47         F(i,1,nn)
48         {
49             ll now=max(d[i],d2[i]);
50             if(now==inf)continue;
51             if(ans>now)
52             {
53                 ans=now;
54                 V.clear();
55                 V.push_back(i);
56             }else if(ans==now)V.push_back(i);
57         }
58         if(ans==inf)printf("Case #%d: Evil John\n",++cas);
59         else 
60         {
61             printf("Case #%d: %lld\n",++cas,ans);
62             int first=1;
63             for(auto it:V)
64             {
65                 if(first)printf("%d",it),first=0;
66                 else printf(" %d",it);
67             }
68             puts("");
69         }
70     }
71     return 0;
72 }