#include <bits/stdc++.h>
using namespace std;
const double eps = 1E-9, oo = 1E5;
double A, B, C;
double ans;
double figure(double y) {
  double x = sqrt(C * C - y * y);
  double a = y, b = x, c = -x * y;
  double sum = (a * A + b * B + c) / C;
  ans = min(ans, sum);
  return sum;
}
void solve(double l, double r) {
  if (l + eps > r) return;
  double lmid = (2 * l + r) / 3, rmid = (l + 2 * r) / 3;
  double lval = figure(lmid), rval = figure(rmid);
  if (lval < rval)
    solve(l, rmid);
  else
    solve(lmid, r);
}
int main() {
  scanf("%lf%lf%lf", &A, &B, &C);
  if (A > B) swap(A, B);
  if (C <= A)
    ans = C;
  else if (C >= A && C <= B)
    ans = A;
  else
    ans = oo, solve(0, C);
  if (ans > 0)
    printf("%.7lf", ans);
  else
    printf("My poor head =(");
  return 0;
}
