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, a[200010];
double f(double x) {
  double maxm = 0, minm = 0, c = 0;
  for (int i = (0); i < (n); i++)
    c += a[i] - x, maxm = max(maxm, c), minm = min(minm, c);
  return maxm - minm;
}
int main() {
  cin >> n;
  for (int i = (0); i < (n); i++) cin >> a[i];
  double l = -1e9, m1, m2, r = 1e9;
  for (int i = (0); i < (200); i++) {
    m1 = l + (r - l) / 3;
    m2 = r - (r - l) / 3;
    if (f(m1) < f(m2))
      r = m2;
    else
      l = m1;
  }
  printf("%lf\n", f(m1));
  return 0;
}
