#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int,int> ii;
typedef pair<double,ii> iii;
const ll MAX=1e9;
int ns;
double raiz(ll x){
double l=0,r=MAX;
for(int i=0;i<=40;i++){
double mid=(l+r)/2;
if(mid*mid>=x)r=mid;
else l=mid;
}
return r;
}
int pa[1010];
void init(int n){
for(int i=0;i<n;i++) pa[i]=i;
ns=n;
}
int findset(int i){
if(pa[i]==i) return pa[i];
return pa[i]=findset(pa[i]);
}
bool issameset(int i,int j){
return findset(i)==findset(j);
}
void unionset(int i,int j){
if(!issameset(i,j)){
int x=findset(i),y=findset(j);
ns--;
pa[x]=y;;
}
}
vector<ii> x;
bool check(double r,int n){
init(n);
//cout<<r<<endl;
for(int i=0;i<n-1;i++){
for(int j=i+1;j<n;j++){
if(!issameset(i,j)){
double a=abs(x[i].first-x[j].first);
double b=abs(x[i].second-x[j].second);
double dist=raiz((a*a)+(b*b));
dist/=2;
// cout<<i<<" "<<j<<" "<<dist<<" "<<r<<" "<<ns<<endl;
if(dist<=r) unionset(i,j);
}
}
}
if(ns==1) return true;
return false;
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
int n;
cin>>n;
for(int i=0;i<n;i++){
int a,b;
cin>>a>>b;
x.push_back(ii(a,b));
}
priority_queue<iii,vector<iii>,greater<iii> > pq;
for(int i=0;i<n-1;i++){
for(int j=i+1;j<n;j++){
double a=abs(x[i].first-x[j].first);
double b=abs(x[i].second-x[j].second);
double dist=sqrt((a*a)+(b*b));
dist/=2;
pq.push(iii(dist,ii(i,j)));
}
}
double mi=-1;
init(n);
while(!pq.empty()){
int u,v;
double dist;
u=pq.top().second.first;
v=pq.top().second.second;
dist=pq.top().first;
pq.pop();
if(!issameset(u,v)){
mi=max(mi,dist);
}
unionset(u,v);
}printf("%.7f\n",mi);
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
364 KB |
Output is correct |
| 2 |
Correct |
1 ms |
364 KB |
Output is correct |
| 3 |
Correct |
1 ms |
364 KB |
Output is correct |
| 4 |
Correct |
1 ms |
492 KB |
Output is correct |
| 5 |
Correct |
2 ms |
492 KB |
Output is correct |
| 6 |
Correct |
39 ms |
2536 KB |
Output is correct |
| 7 |
Correct |
32 ms |
2536 KB |
Output is correct |
| 8 |
Correct |
81 ms |
8804 KB |
Output is correct |
| 9 |
Correct |
148 ms |
8676 KB |
Output is correct |
| 10 |
Correct |
154 ms |
8676 KB |
Output is correct |
