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 N = 2e5 + 8;
int n;
double a[N], q, w, ans, x, l = -N, r = N, m1, m2, mn, mx, sum;
double c(double x) {
  mx = 0, mn = 0, ans = 0, sum = 0;
  for (int i = 0; i < n; i++) {
    sum += (a[i] - x);
    ans = max(ans, max(abs(sum - mx), abs(sum - mn)));
    mn = min(mn, sum);
    mx = max(mx, sum);
  }
  return ans;
}
int main() {
  ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
  cin >> n;
  for (int i = 0; i < n; i++) cin >> a[i];
  for (int i = 0; i < 500; i++) {
    m1 = l + (r - l) / 3;
    m2 = l + (r - l) * 2 / 3;
    if (c(m1) > c(m2))
      l = m1;
    else
      r = m2;
  }
  cout << fixed << setprecision(15) << c(l);
}
