hdu 1875 畅通工程再续

#include<iostream>
#include<vector>
#include<cmath>
#include<cstdio>
#define inf 1<<30
#define maxn 105
using namespace std;
struct stu
{
int x,y;
};
stu mapp[maxn];
int n;
vector<int>root[maxn];
int vaule[maxn][maxn];
int visit[maxn];
void prim()
{
int d[maxn];
fill(d,d+maxn,inf);
fill(visit,visit+maxn,0);
double re=0;
d[0]=0;
int k=0;
while(1)
{
int v=-1;
for(int i=0;i<n;i++)
{
if(!visit[i]&&(v==-1||d[i]<d[v])) v=i;
}
if(v==-1||d[v]==inf) break;
k++;
re+=sqrt(d[v]);
visit[v]=1;
for(int i=0;i<root[v].size();i++)
{
int x=root[v][i];
d[x]=min(d[x],vaule[v][x]);
}
}
if(k==n) printf("%.1lf\n",re*100);
else cout<<"oh!"<<endl;
}
int main()
{
int t;
cin>>t;
while(t--)
{
cin>>n;
for(int i=0;i<maxn;i++) root[i].clear();
for(int i=0;i<n;i++)
{
cin>>mapp[i].x>>mapp[i].y;
for(int j=0;j<i;j++)
{
int l=pow(mapp[i].x-mapp[j].x,2)+pow(mapp[i].y-mapp[j].y,2);
if(l<100||l>1000000) continue;
root[i].push_back(j);
root[j].push_back(i);
vaule[i][j]=l;
vaule[j][i]=l;
}

}
prim();
}
return 0;
}