#include <bits/stdc++.h>
using namespace std;
#define repf(i,k,n) for(int i=k; i<n; i++)
#define rep(i,n) for(int i=0; i<n; i++)
typedef vector<int> vi;
struct DSU{
vi p,size;
DSU(int n){
p.resize(n);
rep(i,n) p[i]=i;
size.assign(n,1);
};
int find(int x){
return (x==p[x] ? x : p[x]=find(p[x]));
}
void join(int a, int b){
int x=find(a), y=find(b);
if(x==y) return;
if(size[x]<size[y]) swap(x,y);
p[x]=y;
size[y]+=size[x];
}
bool isSame(int a, int b){
return find(a)==find(b);
}
int sz(int x){
return size[find(x)];
}
};
bool check(vi &x, vi &y, double r){
int n=x.size();
DSU dsu(n);
rep(i,n){
rep(j,n){
double a=(x[i]-x[j]),
b=(y[i]-y[j]);
if(a*a+b*b<=4*r*r) dsu.join(i,j);
}
}
return dsu.sz(0)==n;
}
int main(){
ios::sync_with_stdio(0); cin.tie(0);
int n; cin>>n;
vi x(n), y(n);
rep(i,n) cin>>x[i]>>y[i];
cout << setprecision(7);
double l=0, r=1e9, e=1e-7;
while(l+e<r){
double m=(l+r)/2;
//cerr << m << '\n';
if(check(x,y,m))
r=m;
else
l=m+e;
}
cout << l << '\n';
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
356 KB |
Output is correct |
2 |
Correct |
0 ms |
356 KB |
Output is correct |
3 |
Correct |
1 ms |
356 KB |
Output is correct |
4 |
Correct |
1 ms |
356 KB |
Output is correct |
5 |
Correct |
1 ms |
448 KB |
Output is correct |
6 |
Correct |
45 ms |
360 KB |
Output is correct |
7 |
Correct |
46 ms |
360 KB |
Output is correct |
8 |
Correct |
93 ms |
472 KB |
Output is correct |
9 |
Correct |
124 ms |
480 KB |
Output is correct |
10 |
Correct |
97 ms |
484 KB |
Output is correct |