#include <bits/stdc++.h>
using namespace std;
const long double eps = 1e-8;
int n, x[200010];
bool check(long double m, bool flag) {
  long double fx = x[0] + 2 * m;
  int i = 0;
  while (i < n && x[i] < fx + eps) i++;
  if (flag) printf("%.6f ", x[0] + (double)m);
  if (i == n) {
    if (flag) printf("%.6f %.6f\n", 1.0 * x[n - 1], 1.0 * x[n - 1]);
    return true;
  }
  fx = x[i] + 2 * m;
  if (flag) printf("%.6f ", x[i] + (double)m);
  while (i < n && x[i] < fx + eps) i++;
  if (i == n) {
    if (flag) printf("%.6f\n", 1.0 * x[n - 1]);
    return true;
  }
  fx = x[i] + 2 * m;
  if (flag) printf("%.6f\n", x[i] + (double)m);
  while (i < n && x[i] < fx + eps) i++;
  return i == n;
}
int main() {
  scanf("%d", &n);
  for (int i = 0; i < (int)(n); i++) scanf("%d", &x[i]);
  sort(x, x + n);
  long double l = 0, r = 1e10, m;
  while (r - l > 1e-7) {
    m = (l + r) * 0.5;
    if (check(m, false))
      r = m;
    else
      l = m;
  }
  printf("%.6f\n", (double)r);
  check(r, true);
}
