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 double EPS = 1e-20;
int n;
int a[200005];
double sum[200005];
double check(double first) {
  double mx = 0;
  double mn = 0;
  sum[0] = 0;
  for (int i = 1; i <= n; i++) {
    sum[i] = sum[i - 1] + (a[i] - first);
    mx = max(mx, sum[i]);
    mn = min(mn, sum[i]);
  }
  return (mx - mn);
}
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  cin >> n;
  for (int i = 1; i <= n; i++) {
    cin >> a[i];
  }
  double l = 0, r = 10;
  for (int rep = 1; rep <= 100; rep++) {
    double u = (2 * l + r) / 3;
    double v = (l + 2 * r) / 3;
    double checkU = check(u);
    double checkV = check(v);
    if (checkU - checkV > EPS) {
      l = u;
    } else {
      r = v;
    }
  }
  cout << setprecision(10) << fixed << check(l);
  return 0;
}
