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;
int n;
double a[maxn];
double cal(double x) {
  double Maxn = 0, Minn = 0;
  double cur = 0;
  for (int i = 0; i < n; i++) {
    cur += a[i] - x;
    Maxn = max(Maxn, cur);
    Minn = min(Minn, cur);
  }
  return Maxn - Minn;
}
int main() {
  scanf("%d", &n);
  for (int i = 0; i < n; i++) scanf("%lf", &a[i]);
  double L = -1e4, R = 1e4;
  for (int i = 0; i < 200; i++) {
    double m1 = (L + R) / 2;
    double m2 = (m1 + R) / 2;
    if (cal(m1) < cal(m2))
      R = m2;
    else
      L = m1;
  }
  printf("%.10f\n", cal(L));
  return 0;
}
