#include <bits/stdc++.h>
using namespace std;
vector<double> v;
bool ok(double mid, bool f) {
  double pos = mid + v[0];
  int indx = upper_bound(v.begin(), v.end(), pos + mid) - v.begin();
  if (f) {
    if (pos > v[v.size() - 1])
      printf("%.6lf ", v[v.size() - 1]);
    else
      printf("%.6lf ", pos);
  }
  if (indx < v.size()) {
    pos = v[indx] + mid;
    indx = upper_bound(v.begin(), v.end(), pos + mid) - v.begin();
  }
  if (f) {
    if (pos > v[v.size() - 1])
      printf("%.6lf", v[v.size() - 1]);
    else
      printf("%.6lf ", pos);
  }
  if (indx < v.size()) {
    pos = v[indx] + mid;
    indx = upper_bound(v.begin(), v.end(), pos + mid) - v.begin();
  }
  if (f) {
    if (pos > v[v.size() - 1])
      printf("%.6lf", v[v.size() - 1]);
    else
      printf("%.6lf ", pos);
  }
  if (pos + mid >= v[v.size() - 1]) {
    return true;
  } else
    return false;
}
double bs() {
  double lo = 0, hi = 1000000000, mid;
  for (int i = 0; i < 100; i++) {
    mid = (lo + hi) / 2;
    if (ok(mid, false)) {
      hi = mid;
    } else
      lo = mid;
  }
  return hi;
}
int main() {
  int n;
  double num, mid;
  scanf("%d", &n);
  while (n--) {
    scanf("%lf", &num);
    v.push_back(num);
  }
  sort(v.begin(), v.end());
  mid = bs();
  printf("%.6lf\n", mid);
  ok(mid, true);
  return 0;
}
