#include <bits/stdc++.h>
using namespace std;
const int N = 2e5 + 7;
const int INF = 1e9 + 7;
int x[N], n;
vector<double> ans;
bool gao(int lim, bool sav = false) {
  int ned = 0;
  for (int l = 0, r; l < n; l = r) {
    for (r = l; r < n && x[r] - x[l] <= lim; r++)
      ;
    if (sav) ans.push_back(x[l] + (x[r - 1] - x[l]) / 2.0);
    ned++;
  }
  return ned <= 3;
}
int main() {
  cin >> n;
  for (int i = (0); i < (n); i++) scanf("%d", &x[i]);
  sort(x, x + n);
  int ret = -1;
  for (int l = 0, r = INF, mid = (l + r) >> 1; l <= mid; mid = (l + r) >> 1) {
    if (gao(mid))
      r = (ret = mid) - 1;
    else
      l = mid + 1;
  }
  gao(ret, true);
  while ((int)((ans).size()) < 3) ans.push_back(ans.back());
  printf("%.10f\n", ret / 2.0);
  for (int i = (0); i < ((int)((ans).size())); i++) printf("%.10f ", ans[i]);
  return 0;
}
