#include <bits/stdc++.h>
using namespace std;
const int maxn = 25005;
const int p = 998244353;
const int inf = 2147483647;
const double eps = 1e-6;
const double pi = 3.1415926576;
const long long INF = 9223372036854775807ll;
int n, x[maxn], y[maxn], dx[maxn], dy[maxn], v[maxn];
double k[maxn], b[maxn], t1, t2, _x, _y;
inline double d(double x1, double y1, double x2, double y2) {
  return sqrt((x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2));
}
inline double g(int i, int j) {
  double dist =
      sqrt((x[i] - x[j]) * (x[i] - x[j]) + (y[i] - y[j]) * (y[i] - y[j]));
  if (dx[i] * dx[j] > 0) {
    t1 = dist / v[i], t2 = dist / v[j];
    if ((x[j] - x[i]) * dx[i] > 0) return t1;
    return t2;
  } else {
    t1 = dist / (v[i] + v[j]);
    if ((x[i] - x[j]) * dx[j] > 0) return t1;
    return 1e100;
  }
}
inline double f(int i, int j) {
  _x = (b[j] - b[i]) / (k[i] - k[j]);
  _y = k[i] * _x + b[i];
  t1 = sqrt((x[i] - _x) * (x[i] - _x) + (y[i] - _y) * (y[i] - _y)) / v[i];
  t2 = sqrt((x[j] - _x) * (x[j] - _x) + (y[j] - _y) * (y[j] - _y)) / v[j];
  if ((_x - x[i]) * dx[i] < 0 || (_x - x[j]) * dx[j] < 0) return 1e100;
  return max(t1, t2);
}
int main() {
  cin >> n;
  for (int i = 0; i < n; i++) cin >> x[i] >> y[i] >> dx[i] >> dy[i] >> v[i];
  double t = 1e100;
  for (int i = 0; i < n; i++)
    k[i] = 1.0 * dy[i] / dx[i], b[i] = y[i] - k[i] * x[i];
  for (int i = 0; i < n; i++)
    for (int j = i + 1; j < n; j++) {
      if (abs(k[i] - k[j]) < eps) {
        if (abs(k[i] - 1.0 * (y[i] - y[j]) / (x[i] - x[j])) < eps)
          t = min(t, g(i, j));
      } else
        t = min(t, f(i, j));
    }
  if (t == 1e100)
    printf("No show :(\n");
  else
    printf("%.10lf\n", t);
  return 0;
}
