10
-405 -230 252 -393 -390 -259 97 163 81 -129
 3
10000 -10000 10000
 1
-10000
 20
-16 -23 29 44 -40 -50 -41 34 -38 30 -12 28 -44 -49 15 50 -28 38 -2 0

702.333333333333712
 10000.000000000016371
 0.000000000000000
 113.875000000000043

#include <bits/stdc++.h>
using namespace std;
int n;
double a[200005], t[200005];
double cal(double x) {
  double ans1 = 0, ans2 = 0, tmp = 0;
  for (int i = 1; i <= n; i++) {
    tmp += (a[i] - x);
    tmp = max(0.0, tmp);
    ans1 = max(ans1, tmp);
  }
  tmp = 0;
  for (int i = 1; i <= n; i++) {
    tmp -= (a[i] - x);
    tmp = max(0.0, tmp);
    ans2 = max(ans2, tmp);
  }
  return max(ans1, ans2);
}
double sf(double beg, double ed) {
  double l = beg, r = ed, m, mm;
  while (r - l > 5e-12) {
    m = (l + r) / 2;
    mm = (m + r) / 2;
    double cm = cal(m);
    double cmm = cal(mm);
    if (cm < cmm)
      r = mm;
    else
      l = m;
  }
  printf("%.15f\n", cal(r));
}
int main() {
  scanf("%d", &n);
  for (int i = 1; i <= n; i++) scanf("%lf", &a[i]);
  sf(-1e4, 1e4);
  return 0;
}
