#include <bits/stdc++.h>
using namespace std;
int l, a, b;
double f(double x) { return a * sin(x) + b * cos(x) - l * sin(x) * cos(x); }
int main() {
  scanf("%d%d%d", &a, &b, &l);
  if (a > b) swap(a, b);
  if (l <= b) {
    printf("%d\n", min(a, l));
    return 0;
  }
  double x = 0, y = 3.1415926535897932384626433832795 * 0.5;
  for (int _ = 0; _ < 200; ++_) {
    double X = (x * 2.0 + y) / 3.0, Y = (x + y * 2.0) / 3.0;
    if (f(X) < f(Y))
      y = Y;
    else
      x = X;
  }
  double ans = f(x);
  if (ans < 1e-8)
    puts("My poor head =(");
  else
    printf("%.10lf\n", ans);
  return 0;
}
