#include <bits/stdc++.h>
using namespace std;
int N;
int X[200002];
double T[3];
int f(double d) {
  int i = 0;
  int lst = X[i];
  T[0] = lst + d;
  while (i < N && X[i] <= T[0] + d) i++;
  if (i == N) return 1;
  lst = X[i];
  T[1] = lst + d;
  while (i < N && X[i] <= T[1] + d) i++;
  if (i == N) return 1;
  lst = X[i];
  T[2] = lst + d;
  while (i < N && X[i] <= T[2] + d) i++;
  if (i == N) return 1;
  return 0;
}
int main(int argc, char **argv) {
  ios::sync_with_stdio(false);
  cin >> N;
  for (int i = 0; i < N; i++) cin >> X[i];
  sort(X, X + N);
  cout << fixed << setprecision(12);
  if (f(0)) {
    cout << 0.0 << endl;
    for (int i = 0; i < 3; i++) cout << T[i] << " ";
    cout << endl;
    return 0;
  }
  f(0.5);
  double l = 0.0, r = (double)1e9;
  for (int i = 0; i < 100; i++) {
    double m = (l + r) / 2;
    if (f(m))
      r = m;
    else
      l = m;
  }
  cout << r << endl;
  for (int i = 0; i < 3; i++) cout << T[i] << " ";
  cout << endl;
  return 0;
}
