#include <bits/stdc++.h>
using namespace std;
const int MAXN = 2 * 100000 + 5;
int n;
long long t[MAXN];
long long res[3];
bool f(long long d) {
  long long prev = 0;
  int j = 0;
  for (int i = 0; i < n; i++) {
    if (t[i] > prev) {
      prev = t[i] + 2 * d;
      res[j++] = t[i] + d;
    }
    if (j > 3) return false;
  }
  while (j < 3) {
    res[j] = res[j - 1];
    j++;
  }
  return true;
}
int main() {
  scanf("%d", &n);
  for (int i = 0; i < n; i++) {
    scanf("%lld", &t[i]);
    t[i] *= 2;
  }
  sort(t, t + n);
  long long l = 0;
  long long r = t[n - 1];
  while (l < r) {
    long long m = (l + r) / 2;
    if (f(m))
      r = m;
    else
      l = m + 1;
  }
  f(l);
  printf("%.6lf\n", double(l) / 2);
  for (int i = 0; i < 3; i++) printf("%.6lf ", double(res[i]) / 2);
  printf("\n");
}
