Agri-Net POJ - 1258

 1 #include <stdio.h>
 2 #include <iostream>
 3 #include <algorithm>
 4 #include <queue>
 5 using namespace std;
 6 const int N = (int)1e3;
 7 const int inf = (int)1e9;
 8 int g[N][N];
 9 int dis[N];
10 bool vis[N];
11 int n;
12 
13 struct node{
14     int loc;
15     int w;
16 
17     bool friend operator<(const node& a,const node& b){
18         return a.w > b.w;
19     }
20 };
21 
22 priority_queue<node > que;
23 
24 int prime(){
25 
26     for(int i = 1; i <= n; i++){
27         vis[i] = 0;
28         dis[i] = inf;
29     }
30 
31     while(!que.empty()) que.pop();
32 
33     que.push(node{1,0});
34     dis[1] = 0;
35 
36     while(!que.empty()){
37         int u = que.top().loc;
38         que.pop();
39         vis[u] = 1;
40 
41         for(int v = 1; v <= n ; v++){
42             if(!vis[v] && dis[v] > g[u][v]){
43                 dis[v] = g[u][v];
44                 que.push(node{v,dis[v]});
45             }
46         }
47     }
48 
49     int ans = 0;
50     for(int i = 1; i <= n; i++)
51         ans += dis[i];
52 
53     return ans;
54 }
55 
56 int main(){
57 
58     while(~scanf("%d",&n) && n){
59 
60         for(int i = 1; i <= n; i++)
61             for(int j = 1; j <= n; j++)
62                 scanf("%d",&g[i][j]);
63 
64         printf("%d\n",prime());
65     }
66 
67     return 0;
68 }