#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
using namespace std;
int main() {
  int n;
  cin >> n;
  int x[n], y[n], dx[n], dy[n], s[n];
  for (int i = 0; i < n; i++) {
    cin >> x[i] >> y[i] >> dx[i] >> dy[i] >> s[i];
  }
  float ans = -1;
  int eff_s;
  float t1, t2;
  for (int i = 0; i < n; i++) {
    for (int j = i + 1; j < n; j++) {
      if (dx[i] * dy[j] == dx[j] * dy[i]) {
        if (dx[i] * (y[j] - y[i]) == dy[i] * (x[j] - x[i])) {
          eff_s = 0;
          if (dy[i] * (y[j] - y[i]) > 0) eff_s += s[i];
          if (dy[j] * (y[i] - y[j]) > 0) eff_s += s[j];
          if (eff_s != 0) {
            t1 = sqrt((y[j] - y[i]) * (y[j] - y[i]) +
                      (x[j] - x[i]) * (x[j] - x[i])) /
                 eff_s;
            if (ans == -1 || ans > t1) {
              ans = t1;
            }
          }
        }
      } else {
        t1 = (sqrt(dx[i] * dx[i] + dy[i] * dy[i]) *
              (dy[j] * (x[j] - x[i]) - dx[j] * (y[j] - y[i]))) /
             (s[i] * (dx[i] * dy[j] - dx[j] * dy[i]));
        t2 = (sqrt(dx[j] * dx[j] + dy[j] * dy[j]) *
              (dy[i] * (x[i] - x[j]) - dx[i] * (y[i] - y[j]))) /
             (s[j] * (dx[j] * dy[i] - dx[i] * dy[j]));
        if (t1 >= 0 && t2 >= 0 && (ans == -1 || ans > max(t1, t2))) {
          ans = max(t1, t2);
        }
      }
    }
  }
  if (ans == -1)
    cout << "No show :(";
  else
    cout << setprecision(14) << ans;
  return 0;
}
