#include <bits/stdc++.h>
using namespace std;
const double inf = 1e14;
const double pi = acos(-1);
const double eps = 1e-10;
const int maxn = 25010;
int n, x[maxn], y[maxn], dx[maxn], dy[maxn], s[maxn];
double ans = inf, ddx[maxn], ddy[maxn], K[maxn], B[maxn];
inline double solve(int a, int b) {
  double b1, k1, b2, k2;
  k1 = K[a];
  b1 = B[a];
  k2 = K[b];
  b2 = B[b];
  if (k1 == k2) {
    double kk =
        sqrt((x[a] - x[b]) * (x[a] - x[b]) + (y[a] - y[b]) * (y[a] - y[b]));
    double X, Y, XX, YY, t;
    t = kk / double(s[a] + s[b]);
    X = (double)x[a] + (double)ddx[a] * t * s[a];
    Y = (double)y[a] + (double)ddy[a] * t * s[a];
    XX = (double)x[b] + (double)ddx[b] * t * s[b];
    YY = (double)y[b] + (double)ddy[b] * t * s[b];
    if (abs(X - XX) <= eps && abs(Y - YY) <= eps) return t;
    if (s[a] == s[b]) return inf;
    t = kk / double(s[a]);
    X = (double)x[a] + (double)ddx[a] * t * s[a];
    Y = (double)y[a] + (double)ddy[a] * t * s[a];
    if (abs(X - x[b]) <= eps && abs(Y - y[b]) <= eps) return t;
    t = kk / double(s[b]);
    X = (double)x[b] + (double)ddx[b] * t * s[b];
    Y = (double)y[b] + (double)ddy[b] * t * s[b];
    if (abs(X - x[a]) <= eps && abs(Y - y[a]) <= eps) return t;
    return inf;
  }
  double X = (b2 - b1) / (k1 - k2), Y;
  Y = k1 * X + b1;
  if ((Y - y[a]) * dy[a] < 0) return inf;
  if ((Y - y[b]) * dy[b] < 0) return inf;
  if ((X - x[a]) * dx[a] < 0) return inf;
  if ((X - x[b]) * dx[b] < 0) return inf;
  double now1 = sqrt((X - x[a]) * (X - x[a]) + (Y - y[a]) * (Y - y[a])) / s[a];
  double now2 = sqrt((X - x[b]) * (X - x[b]) + (Y - y[b]) * (Y - y[b])) / s[b];
  return max(now1, now2);
}
int main() {
  scanf("%d", &n);
  for (int i = 1; i <= n; ++i) {
    scanf("%d%d%d%d%d", &x[i], &y[i], &dx[i], &dy[i], &s[i]);
    double v = sqrt(dx[i] * dx[i] + dy[i] * dy[i]);
    ddx[i] = dx[i] / v;
    ddy[i] = dy[i] / v;
    K[i] = (double)dy[i] / dx[i];
    B[i] = y[i] - (double)dy[i] / dx[i] * x[i];
  }
  for (int i = 1; i <= n; ++i)
    for (int j = i + 1; j <= n; ++j) {
      ans = min(ans, solve(i, j));
    }
  if (ans > 1e12)
    printf("No show :(\n");
  else
    printf("%.15f\n", ans);
  return 0;
}
