用prim能过，用ku...超时

ku...

#include<iostream>
using namespace std;struct town{int x;int y;
}town[800];struct dist{int from;int to;int dis;int vis;
}dist[320000];int cmp(const void *a, const void *b)
{return (*(struct dist *)a).dis > (*(struct dist *)b).dis ? 1 : -1;
}int fa[800];
int find(int x)
{if(x == fa[x])return x;fa[x] = find(fa[x]);return fa[x];
}int main()
{int N, M, i;cin>>N;for(i=0;i<N;i++){cin>>town[i].x>>town[i].y;}cin>>M;for(i=0;i<M;i++){cin>>dist[i].from>>dist[i].to;dist[i].dis = 0;dist[i].vis = 0;}int j, k;i = M;for(j=0;j<N;j++){for(k=j+1;k<N;k++){dist[i].vis = 1;dist[i].from = j+1;dist[i].to = k + 1;dist[i].dis = (town[j].x-town[k].x)*(town[j].x-town[k].x) + (town[j].y-town[k].y)*(town[j].y-town[k].y);i++;}}int num = M+N*(N-1)/2;qsort(dist, num, sizeof(dist[0]), cmp);for(i=1;i<=N;i++)fa[i]=i;int count = 0;for(i=0;i<num;i++){if(find(dist[i].from) != find(dist[i].to)){fa[find(dist[i].from)] = find(dist[i].to);count++;if(dist[i].vis)cout<<dist[i].from<<" "<<dist[i].to<<endl;if(count == N-1)break; }}system("pause");return 0;
}

prim

#include<iostream>
#include<climits>
#include<cstring>
using namespace std;struct node{int x, y;
}node[755];int maxEdge=INT_MAX;
int flag[755];
int pre[755];
int dist[755];int map[755][755];
int main()
{int N, M;cin>>N;for(int i=1;i<=N;i++){cin>>node[i].x>>node[i].y;}memset(map, 0, sizeof(map));for(int i=1;i<=N;i++){for(int j=1;j<=N;j++){map[i][j]=(node[i].x-node[j].x)*(node[i].x-node[j].x)+(node[i].y-node[j].y)*(node[i].y-node[j].y);}}for(int i=0;i<=N;i++){flag[i]=0;dist[i]=maxEdge;pre[i]=1;}cin>>M;for(int i=1;i<=M;i++){int a, b;cin>>a>>b;pre[b] = a;map[a][b]=0;map[b][a]=0;   }flag[1]=1;dist[1]=maxEdge;  for(int j=2;j<=N;j++){dist[j]=map[1][j];}int next,p=1; for(int i=1;i<N;i++){  int min=maxEdge; for(int j=1;j<=N;j++){if(dist[j]<min){min=dist[j];next = j;}                  }p=pre[next];flag[next]=1;dist[next]=maxEdge;pre[next]=p;if(map[pre[next]][next]  != 0){cout<<pre[next]<<" "<<next<<endl;}for(int j=1;j<=N;j++){if((map[next][j] < dist[j])&& flag[j]==0){dist[j]=map[next][j];pre[j]=next;}}           }system("pause");return 0;
}