#include <bits/stdc++.h>
using namespace std;
int n, a[200009];
bool double_compare(int a, double b) {
  double tmp = (b + (1e-7)) * 1000000.0;
  long long tmp2 = tmp, tmp3 = (long long)a * 1000000;
  return tmp3 > tmp2;
}
bool valid(double d) {
  double pos = (double)(a[0]) + d;
  int num = 1;
  for (int i = 1; i < n; ++i) {
    double tmp = (pos + d) * 1000000.0;
    long long tmp2 = tmp, tmp3 = (long long)a[i] * 1000000;
    if (tmp3 > tmp2) {
      ++num;
      pos = (double)(a[i]) + d;
    }
  }
  return num <= 3;
}
void print_pos(double d) {
  double pos = (double)(a[0]) + d;
  printf("%.6lf", pos);
  int num = 1;
  for (int i = 1; i < n; ++i) {
    if (double_compare(a[i], pos + d)) {
      ++num;
      pos = (double)(a[i]) + d;
      printf(" %.6lf", pos);
    }
  }
  while (num < 3) ++num, printf(" %.6lf", pos);
  printf("\n");
}
int main() {
  scanf("%d", &n);
  for (int i = 0; i < n; ++i) {
    scanf("%d", &a[i]);
  }
  sort(a, a + n);
  double s = 0, e = 2e10;
  for (double mid = (e - s) / 2; mid >= 1e-8; mid *= 0.5) {
    if (!valid(s + mid)) s += mid;
  }
  printf("%.6lf\n", s);
  print_pos(s);
  return 0;
}
