#include <bits/stdc++.h>
using namespace std;
int x[250005], y[250005], dx[250005], dy[250005];
double s[250005];
double sovle(int a, int b) {
  int notParallel = dx[a] * dy[b] - dx[b] * dy[a];
  if (notParallel) {
    double ta =
        ((x[b] - x[a]) * dy[b] - (y[b] - y[a]) * dx[b]) / (s[a] * notParallel);
    double tb =
        ((y[a] - y[b]) * dx[a] - (x[a] - x[b]) * dy[a]) / (s[b] * notParallel);
    if (ta < 0 || tb < 0)
      return -1;
    else
      return max(ta, tb);
  } else {
    if ((x[b] - x[a]) * dy[a] != (y[b] - y[a]) * dx[a]) return -1;
    int a2b = (x[b] - x[a]) * dx[a], b2a = (x[a] - x[b]) * dx[b];
    if (a2b > 0 && b2a > 0)
      return (x[b] - x[a]) / (s[a] * dx[a] - s[b] * dx[b]);
    else if (a2b > 0)
      return (x[b] - x[a]) / s[a] / dx[a];
    else if (b2a > 0)
      return (x[a] - x[b]) / s[b] / dx[b];
    else
      return -1;
  }
}
int main() {
  int n;
  double now, ans = -1;
  scanf("%d", &n);
  for (int i = 0; i < n; i++) {
    scanf("%d%d%d%d%lf", &x[i], &y[i], &dx[i], &dy[i], &s[i]);
    s[i] /= sqrt(dx[i] * dx[i] + dy[i] * dy[i]);
  }
  for (int i = 0; i < n; i++) {
    for (int j = i + 1; j < n; j++) {
      now = sovle(i, j);
      if (now >= 0)
        if (ans < 0)
          ans = now;
        else
          ans = min(ans, now);
    }
  }
  if (ans < 0)
    printf("No show :(");
  else
    printf("%.7f", ans);
}
