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], b[200005], r = -10005, l = 10005, midl, midr, sum, ans;
double weakn(double m) {
  ans = 0;
  sum = 0;
  for (int i = 0; i < n; i++) {
    sum += a[i] - m;
    if (sum < 0) sum = 0;
    ans = max(ans, sum);
  }
  sum = 0;
  for (int i = 0; i < n; i++) {
    sum += m - a[i];
    if (sum < 0) sum = 0;
    ans = max(ans, sum);
  }
  return ans;
}
int main() {
  scanf("%d", &n);
  for (int i = 0; i < n; i++) {
    scanf("%lf", &a[i]);
    if (a[i] > r) r = a[i];
    if (a[i] < l) l = a[i];
  }
  while (r - l > 2e-12) {
    midl = (l + r) / 2;
    midr = (midl + r) / 2;
    if (weakn(midl) < weakn(midr))
      r = midr;
    else
      l = midl;
  }
  printf("%lf", weakn(l));
}
