#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, p[200000];
  scanf("%d", &n);
  for (int i = 0; i < (int)(n); i++) scanf("%d", p + i);
  sort(p, p + n);
  double a = 0.0, b = (double)(p[n - 1] - p[0]) / 3.0 + 1;
  double t[3], m;
  for (int i = 0; i < (int)(3); i++) t[i] = 0.0;
  while (b - a > 1e-10) {
    m = (a + b) / 2.0;
    int base = 0;
    t[0] = p[0] + m;
    for (int i = 0; i < (int)(n); i++) {
      if ((double)p[i] - 1e-10 >= t[base] + m) {
        if (base == 2) {
          a = m;
          goto NEXT;
        }
        t[++base] = p[i] + m;
      }
    }
    b = m;
  NEXT:;
  }
  int base = 0;
  t[0] = p[0] + m;
  for (int i = 0; i < (int)(n); i++) {
    if (p[i] > t[base] + m + 1e-7) t[++base] = p[i] + m;
  }
  printf("%.6lf\n%.6lf %.6lf %.6lf\n", m, t[0], t[1], t[2]);
  return 0;
}
