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;
const int MAXN = 200010;
double value[MAXN];
int n;
double fun(double x) {
  double mn = 0, mx = 0, sum = 0;
  for (int i = 0; i < n; i++) {
    sum += (value[i] - x);
    mn = min(sum, mn);
    mx = max(sum, mx);
  }
  return (mx - mn);
}
int main() {
  cin >> n;
  for (int i = 0; i < n; i++) {
    cin >> value[i];
  }
  double l = -10000.0, r = 10000.0;
  for (int i = 0; i < 100; i++) {
    double m1 = l + (r - l) / 3.0;
    double m2 = r - (r - l) / 3.0;
    if (fun(m1) < fun(m2))
      r = m2;
    else
      l = m1;
  }
  cout << fixed << setprecision(6) << fun(l) << endl;
  return 0;
}
