#include <cstdio>
#include <algorithm>
#include <cmath>

double macos(double x) {
  if (x < -1) x = -1;
  if (x > 1) x = 1;
  return acos(x);
}

double area(double a, double b, double c) {
  double p = (a + b + c) * .5;
  return sqrt(p * (p - a) * (p - b) * (p - c));
}

double segment(double r, double ang, double s) {
  return .5 * r * r * (ang - s);
}

double getArea(double r1, double r2, double r3) {
  double a = r2 + r3;
  double b = r1 + r3;
  double c = r1 + r2;
  double c1 = -(a * a - b * b - c * c) * .5 / b / c;
  double c2 = -(b * b - a * a - c * c) * .5 / a / c;
  double c3 = -(c * c - a * a - b * b) * .5 / a / b;
  double ang1 = macos(c1);
  double ang2 = macos(c2);
  double ang3 = macos(c3);
  double s1 = sin(ang1);
  double s2 = sin(ang2);
  double s3 = sin(ang3);
  double aa = 2 * r1 * sin(ang1 * .5);
  double bb = 2 * r2 * sin(ang2 * .5);
  double cc = 2 * r3 * sin(ang3 * .5);
  return area(aa, bb, cc) - segment(r1, ang1, s1) - segment(r2, ang2, s2) - segment(r3, ang3, s3);
}

double getFourth(double r1, double r2, double r3) {
  double l = 0;
  double r = std::min(std::min(r1, r2), r3);
  for (int it = 0; it < 300; it++) {
    double mid = (l + r) * .5;
    if (area(r1 + r2, r1 + mid, r2 + mid) + area(r1 + r3, r1 + mid, r3 + mid) + area(r2 + r3, r2 + mid, r3 + mid) > area(r1 + r2, r1 + r3, r2 + r3)) {
      r = mid;
    } else {
      l = mid;
    }
  }
  return (l + r) * .5;
}

int a[12345];

int main() {
  for (int i = 1; i <= 6; i++) {
    for (int j = i; j <= 6; j++) {
      for (int k = j; k <= 6; k++) {
        printf("%d %d %d %.17lf\n", i, j, k, getFourth(i, j, k));
      }
    }
  }
  return 0;
  int n;
  scanf("%d", &n);
  for (int i = 0; i < n; i++) scanf("%d", a + i);
  if (n > 4) {
    puts("-1");
    return 0;
  }
  std::sort(a, a + n);
  double ans = 0;
  for (int i = 0; i < n; i++) ans += M_PI * a[i] * a[i];
  if (n <= 3) {
    if (n == 3) ans += getArea(a[0], a[1], a[2]);
    printf("%.17lf\n", ans);
    if (n == 3) {
      double r4 = getFourth(a[0], a[1], a[2]);
      int c = getchar();
      while (c <= 32 && c >= 0) c = getchar();
      if (c < 0) return 0;
      printf("%.17lf\n", r4);
    }
  } else if (n == 4) {
    ans = 0;
    for (int i = 1; i < n; i++) ans += M_PI * a[i] * a[i];
    ans += getArea(a[1], a[2], a[3]);
    double r4 = getFourth(a[1], a[2], a[3]);
    double dif = a[0] - r4;
    if (dif < 0) dif = -dif;
    if (dif > 1e-8) puts("-1"); else {
      printf("%.17lf\n", ans);
    }
  }
}