#include<bits/stdc++.h>
using namespace std;
#pragma GCC optimize("O3")
#define tof_io ios_base::sync_with_stdio(false);cin.tie(0) , cout.tie(0);
#define double long double
#define int long long
#define pb push_back
#define all(x) x.begin(),x.end()
#define endl '\n'
#define sz(x) x.size()
const int mod = 1e9 + 7; //998244353 1e9+7 1e9+9
const int N = 2e4 + 1;
const int lg = 23;
const int eps = 1e-9;
const int inf = 1e9;
int fac[N];
int inv[N];
int n, timer = 0;
double x[N], y[N];
bool vis[N];
double ans = 0;
int dnt_pow (int a, int b, int md = mod){int ans = 1; while(b){if(b&1){ans = (a*ans)%md;}a = (a*a)%md;b >>= 1;}return ans ;}
void dnt_bld (){fac[0] = 1; inv[0] = dnt_pow(fac[0],mod-2) ;for(int i = 1 ; i < N ; i++) {fac[i] = (fac[i-1] * i) % mod;inv[i] = dnt_pow( fac[i] , mod-2);}}
int dnt_ncr (int r,int n){if(r>n) return 0; return fac[n] * inv[r] % mod * inv[n-r] % mod;}
void dfs(int v, double r)
{
if (vis[v])
return;
timer++;
vis[v] = 1;
for (int i = 0; i < n; i++)
{
if (i != v and vis[i] == 0)
{
if((x[i] - x[v]) * (x[i] - x[v]) + (y[i] - y[v]) * (y[i] - y[v]) <= (r * r + 2 * r * r + r * r))
{
dfs(i,r);
}
}
}
}
int32_t main()
{
cin >> n;
for (int i = 0; i < n; i++)
{
cin >> x[i] >> y[i];
}
double l = 0;
double r = inf;
for (int i = 0; i <= 64; i++)
{
double mid = (l + r) / 2.0;
timer = 0;
dfs(0 , mid);
if (timer == n)
{
r = mid - eps;
ans = mid;
}
else
{
l = mid + eps;
}
for (int i = 0; i < n; i++) vis[i] = 0;
}
cout << fixed << setprecision(6) << ans;
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
0 ms |
348 KB |
Output is correct |
| 2 |
Correct |
0 ms |
348 KB |
Output is correct |
| 3 |
Correct |
1 ms |
348 KB |
Output is correct |
| 4 |
Correct |
2 ms |
604 KB |
Output is correct |
| 5 |
Correct |
2 ms |
348 KB |
Output is correct |
| 6 |
Correct |
22 ms |
504 KB |
Output is correct |
| 7 |
Correct |
30 ms |
348 KB |
Output is correct |
| 8 |
Correct |
79 ms |
348 KB |
Output is correct |
| 9 |
Correct |
151 ms |
556 KB |
Output is correct |
| 10 |
Correct |
181 ms |
552 KB |
Output is correct |
