HDU 1009 The Shortest Path in Nya Graph

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  1 #include <iostream>  2 #include <cstdio>  3 #include <cstring>  4 #include <algorithm>  5 #include <cmath>  6 #include <queue>  7 #include <vector>  8   9 #define LL __int64 10  11 const LL INF = 2000000000; 12  13 using namespace std; 14  15 LL dis[300100]; 16  17 int head[300100]; 18  19 struct E 20 { 21     int u,v,w,next; 22 }edge[1001000]; 23  24 int top; 25  26 void link(int u,int v,int w) 27 { 28     edge[top].u = u; 29     edge[top].v = v; 30     edge[top].w = w; 31     edge[top].next = head[u]; 32     head[u] = top++; 33 } 34  35 struct HeapNode 36 { 37     int d,u; 38     bool operator < (const HeapNode& rhs) const{ 39         return d>rhs.d; 40     } 41 }; 42  43 void dij(int st,int n) 44 { 45     priority_queue<HeapNode> q; 46  47     HeapNode p; 48  49     p.d = 0; 50     p.u = 1; 51  52     q.push(p); 53  54     while(q.empty() == false) 55     { 56         HeapNode x = q.top(); 57         q.pop(); 58  59         int u = x.u; 60  61         st = head[u]; 62  63         while(st != -1) 64         { 65             if(dis[u] + edge[st].w < dis[edge[st].v]) 66             { 67                 dis[edge[st].v] = edge[st].w + dis[u]; 68  69                 HeapNode temp; 70  71                 temp.d = dis[edge[st].v]; 72                 temp.u = edge[st].v; 73                 q.push(temp); 74             } 75             st = edge[st].next; 76  77         } 78     } 79  80     if(dis[n] == INF) 81         cout<<"-1"<<endl; 82     else 83         cout<<dis[n]<<endl; 84 } 85  86 int main() 87 { 88     int i,n,m,c,u,v,w; 89     int T,icase = 0; 90  91     cin>>T; 92     while(T--) 93     { 94         scanf("%d %d %d",&n,&m,&c); 95  96         memset(head,-1,(n*3+2)*sizeof(int)); 97  98         top = 0; 99 100         for(i = 1;i <= n; ++i)101         {102             scanf("%d",&u);103 104             link(n+2*u-1,i,0);105             link(i,n+u*2,0);106         }107 108         for(i = 1;i < n; ++i)109         {110             link(n+i*2+2,n+i*2-1,c);111             link(n+i*2,n+i*2+1,c);112         }113 114         for(i = 1;i <= m; ++i)115         {116             scanf("%d %d %d",&u,&v,&w);117             link(u,v,w);118             link(v,u,w);119         }120 121         for(i = 1,n *= 3;i <= n; ++i)122         {123             dis[i] = INF;124         }125 126         dis[1] = 0;127 128         printf("Case #%d: ",++icase);129         dij(1,n/3);130 131     }132     return 0;133 }
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