# include <bits/stdc++.h>
using namespace std;
const double eps = 1e-8;
const int N = 1e3+5;
int n, components, f[N], de[N];
double x[N], y[N];
int find(int u) {return f[u]==u? u: f[u] = find(f[u]);}
void unite(int u, int v) {
int fu = find(u), fv = find(v);
if (fu==fv) return ;
if (de[fu] < de[fv]) swap(fu, fv);
--components;
f[fv] = fu;
de[fu] = max(de[fu], de[fv]+1);
}
bool close(int u, int v, double R) {
return (x[u]-x[v])*(x[u]-x[v]) + (y[u]-y[v])*(y[u]-y[v]) <= 4.0*R*R;
}
bool check(double R) {
components = n;
iota(f+1, f+1+n, 1);
fill(de+1, de+1+n, 0);
for (int i=1; i<=n; ++i) {
for (int j=1; j<=n; ++j) {
if (close(i, j, R)) unite(i, j);
}
}
return components == 1;
}
int main() {
cin >> n;
for (int i=1; i<=n; ++i) cin >> x[i] >> y[i];
double l = 0, r = 1e9+7;
while (l + eps < r) {
double mid = (l+r)/2.0;
if (check(mid)) r = mid;
else l = mid;
}
cout << setprecision(8) << r << '\n';
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
344 KB |
Output is correct |
2 |
Correct |
1 ms |
352 KB |
Output is correct |
3 |
Correct |
1 ms |
352 KB |
Output is correct |
4 |
Correct |
2 ms |
348 KB |
Output is correct |
5 |
Correct |
1 ms |
436 KB |
Output is correct |
6 |
Correct |
53 ms |
436 KB |
Output is correct |
7 |
Correct |
50 ms |
432 KB |
Output is correct |
8 |
Correct |
136 ms |
440 KB |
Output is correct |
9 |
Correct |
116 ms |
684 KB |
Output is correct |
10 |
Correct |
100 ms |
344 KB |
Output is correct |