[HNU4]Dwarf Tower

 1 #include <cstdio>
 2 #include <cstdlib>
 3 #include <cstring>
 4 #include <algorithm>
 5 #include <iostream>
 6 #include <cmath>
 7 #include <queue>
 8 #include <map>
 9 #include <stack>
10 #include <list>
11 #include <vector>
12 using namespace std;
13 #define LL __int64
14 struct node
15 {
16     int x,y;
17     node(LL a,LL b):x(a),y(b){}
18 };
19 LL a[100010];
20 int vis[100010];
21 vector <node>v[10010];
22 int n,m,i,j,k,x,y;
23 queue<int>q;
24 int main()
25 {
26         scanf("%d%d",&n,&m);
27         for (i=1;i<=n;i++)
28         {
29             scanf("%I64d",&a[i]);
30             vis[i]=0;
31         }
32         if (m==0)
33         {
34             printf("%I64d\n",a[1]);
35             return 0;
36         }
37         for (i=1;i<=m;i++)
38         {
39             scanf("%d%d%d",&k,&x,&y);
40             v[x].push_back(node(y,k));
41             v[y].push_back(node(x,k));
42             if (!vis[x])
43             {
44                 vis[x]=1;
45                 q.push(x);
46             }
47             if (!vis[y])
48             {
49                 vis[y]=1;
50                 q.push(y);
51             }
52         }
53         while (!q.empty())
54         {
55             k=q.front();
56             vis[k]=0;
57             q.pop();
58             int l=v[k].size();
59             for (i=0;i<l;i++)
60             {
61                 if (a[k]+a[v[k][i].x]<a[v[k][i].y])
62                 {
63                     a[v[k][i].y]=a[k]+a[v[k][i].x];
64                     if (!vis[v[k][i].y])
65                     {
66                         q.push(v[k][i].y);
67                         vis[v[k][i].y]=1;
68                     }
69                 }
70             }
71         }
72         printf("%I64d\n",a[1]);
73         return 0;
74 }