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 arr[200005];
double Poorness(double x) {
  double sum, maxs = -10000.0;
  int i = 0, count;
  while (i < n) {
    sum = arr[i];
    count = 1;
    if (sum >= x) {
      while (++i < n && arr[i] >= x) {
        sum += arr[i];
        count++;
      }
    } else {
      while (++i < n && arr[i] <= x) {
        sum += arr[i];
        count++;
      }
    }
    maxs = max(maxs, fabs(sum - x * count));
  }
  return maxs;
}
int main() {
  scanf("%d", &n);
  int i;
  double low = 10000.0, high = -10000.0;
  for (i = 0; i < n; i++) {
    scanf("%lf", arr + i);
    low = min(low, arr[i]);
    high = max(high, arr[i]);
  }
  double lmid, hmid;
  i = 200;
  while (i--) {
    lmid = (low + high) / 2.0;
    hmid = (lmid + high) / 2.0;
    if (Poorness(lmid) < Poorness(hmid))
      high = hmid;
    else
      low = lmid;
  }
  printf("%.15lf\n", Poorness((low + high) / 2.0));
  return 0;
}
