#include <bits/stdc++.h>
using namespace std;
const int maxn = 2e5 + 100;
int v[maxn];
int n;
vector<double> ans1;
bool check(double d) {
  double last = -3e9;
  int cnt = 0;
  vector<double> a;
  for (int i = 0; i < n; i++) {
    if (a.empty() || (v[i] - a.back() > d)) {
      a.push_back(v[i] + d);
    }
  }
  if (a.size() > 3) return false;
  while (a.size() < 3) a.push_back(a.back());
  ans1 = a;
  return true;
}
int main() {
  scanf("%d", &n);
  for (int i = 0; i < n; i++) {
    scanf("%d", &v[i]);
  }
  sort(v, v + n);
  double lo = 0;
  double hi = 2e9;
  double ans = 0;
  for (int it = 0; it < 300; it++) {
    double mid = (lo + hi) / 2;
    if (check(mid)) {
      ans = mid;
      hi = mid;
    } else
      lo = mid;
  }
  printf("%.6lf\n", ans);
  sort(ans1.begin(), ans1.end());
  for (int i = 0; i < 3; i++) {
    printf("%.6lf ", ans1[i]);
  }
  puts("");
  return 0;
}
