HDU 1875 畅通工程再续

#include<cstdio>
#include<cstring>
#include<string>
#include<cmath>
#include<iostream>
#include<algorithm>
#include<set>
#define LL long long
#define db double
#define maxn 10000000
#define EPS 1e-15
#define max(a,b) ((a>b)?(a):(b))
#define min(a,b) ((a<b)?(a):(b))
using namespace std;

int p[15000],x[200],y[200];
struct all
{
int u,v,r;
double w;
}e[15000];
int cmp(all x,all y){
return x.w<y.w;
}
db f(int x1,int x2,int y1,int y2){
return sqrt((db)((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2)));
}
int find(int x){
while (x!=p[x]) x=p[x];
return x;
}
int main(){
int T;
scanf("%d",&T);
while (T--){
int k,cnt=1,sum=0;
double ans=0;
scanf("%d",&k);
for (int i=1;i<=k;i++) scanf("%d%d",&x[i],&y[i]);
for (int i=1;i<k;i++)
for (int j=1;j<=k;j++){
db tmp;
tmp=f(x[i],x[j],y[i],y[j]);
if (tmp>=10.0 && tmp<=1000.0){
e[cnt].u=i;
e[cnt].v=j;
e[cnt].w=tmp;
cnt++;
}
}
for (int i=1;i<=cnt;i++) p[i]=i;
sort(e+1,e+cnt,cmp);
for (int i=1;i<=cnt;i++){
int X=find(e[i].u);
int Y=find(e[i].v);
if (X!=Y){
ans+=e[i].w;
p[X]=Y;
sum++;
}
}
if (sum==k-1) printf("%.1lf\n",ans*100);
else printf("oh!\n");
}
return 0;
}