#include <bits/stdc++.h>
using namespace std;
vector<double> v, point;
set<double> s;
bool check(double x, bool fl) {
  int i = 0, k, j;
  int cnt = 0;
  for (k = 0; k < 3; k++) {
    double base = v[i] + x;
    for (j = i; j < v.size(); j++) {
      if (v[j] <= base) continue;
      if ((v[j] - base - x) <= 0)
        continue;
      else {
        cnt++;
        i = j;
        break;
      }
    }
    if (j < v.size() && k == 2 && !fl) {
      point.clear();
      return false;
    }
    point.push_back(base);
  }
  return true;
}
void make(double r) {
  sort(v.begin(), v.end());
  point.clear();
  int i = 0, j, tmp = i;
  double b1 = v[0] + r;
  point.push_back(v[0] + r);
  i = upper_bound(v.begin(), v.end(), b1 + r) - v.begin();
  if (fabs(v[i] - b1 - r) < 1e-12 && i < v.size() - 1) i += 1;
  if (tmp == i) i += 1;
  b1 = v[i] + r;
  point.push_back(b1);
  tmp = i;
  i = upper_bound(v.begin(), v.end(), b1 + r) - v.begin();
  if (fabs(v[i] - b1 - r) < 1e-12 && i < v.size() - 1) i += 1;
  if (tmp == i) i += 1;
  b1 = v[i] + r;
  point.push_back(b1);
}
double fn() {
  double l = 0, h = 2e9, m;
  for (long long i = 0; i < 300; i++) {
    m = (l + h) / 2.0;
    if (fabs(h - l) < 1e-12) {
      break;
    };
    if (check(m, false)) {
      point.clear();
      h = m;
    } else
      l = m;
  }
  make(m);
  return m;
}
int main() {
  int t, tc = 0;
  long long n;
  while (1 == scanf("%lld", &n)) {
    double x, ans;
    for (long long i = 0; i < n; ++i) {
      scanf("%lf", &x);
      s.insert(x);
    }
    v = vector<double>(s.begin(), s.end());
    if (true)
      ans = fn();
    else {
      puts("0.000000");
      for (auto i : s) printf("%.6f ", (double)i);
      puts("");
      s.clear();
      continue;
    }
    printf("%.6f\n", ans);
    ++tc;
    for (int i = 0; i < point.size(); i++) printf("%.6f ", point[i]);
    if (point.size() < 3)
      for (int i = 0; i < 3 - point.size(); i++) printf("%.6f ", point[0]);
    puts("");
    s.clear();
  }
  return 0;
}
