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

""" Python 3 compatibility tools. """
from __future__ import division, print_function
import itertools
import sys
import os
from io import BytesIO, IOBase


if sys.version_info[0] < 3:
  input = raw_input
  range = xrange

  filter = itertools.ifilter
  map = itertools.imap
  zip = itertools.izip


def is_it_local():
  script_dir = str(os.getcwd()).split('/')
  username = "dipta007"
  return username in script_dir


def READ(fileName):
  if is_it_local():
    sys.stdin = open(f'./{fileName}', 'r')

# region fastio
BUFSIZE = 8192

class FastIO(IOBase):
  newlines = 0

  def __init__(self, file):
    self._fd = file.fileno()
    self.buffer = BytesIO()
    self.writable = "x" in file.mode or "r" not in file.mode
    self.write = self.buffer.write if self.writable else None

  def read(self):
    while True:
      b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
      if not b:
          break
      ptr = self.buffer.tell()
      self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
    self.newlines = 0
    return self.buffer.read()

  def readline(self):
    while self.newlines == 0:
      b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
      self.newlines = b.count(b"\n") + (not b)
      ptr = self.buffer.tell()
      self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
    self.newlines -= 1
    return self.buffer.readline()

  def flush(self):
    if self.writable:
      os.write(self._fd, self.buffer.getvalue())
      self.buffer.truncate(0), self.buffer.seek(0)


class IOWrapper(IOBase):
  def __init__(self, file):
    self.buffer = FastIO(file)
    self.flush = self.buffer.flush
    self.writable = self.buffer.writable
    self.write = lambda s: self.buffer.write(s.encode("ascii"))
    self.read = lambda: self.buffer.read().decode("ascii")
    self.readline = lambda: self.buffer.readline().decode("ascii")

if not is_it_local():
  sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout)
  input = lambda: sys.stdin.readline().rstrip("\r\n")

# endregion


def input1(type=int):
  return type(input())


def input2(type=int):
  [a, b] = list(map(type, input().split()))
  return a, b


def input3(type=int):
  [a, b, c] = list(map(type, input().split()))
  return a, b, c


def input_array(type=int):
  return list(map(type, input().split()))


def input_string():
  s = input()
  return list(s)

if is_it_local():
  def debug(*args):
    st = ""
    for arg in args:
      st += f"{arg} "
    print(st)
else:
  def debug(*args):
    pass

##############################################################

arr = []

def fun(x):
  cum = 0
  res = 0
  for v in arr:
    nw = (v-x)
    cum += nw
    cum = max(cum, 0)
    res = max(res, cum)
    # print(v, nw, cum, res)
  
  cum = 0
  for v in arr:
    nw = -(v-x)
    cum += nw
    cum = max(cum, 0)
    res = max(res, cum)
    # print(v, nw, cum, res)
  
  return res

def main():
  global arr
  n = input1()
  arr = input_array()

  low = -10000
  high = 10000
  loop = 100
  # print(fun(2.0))
  # return
  while loop > 0:
    loop -= 1

    m1 = ( low * 2.0 + high ) / 3.0
    m2 = ( low + high * 2.0) / 3.0
    y1 = fun(m1)
    y2 = fun(m2)

    # print(y1, y2)

    if y1 > y2:
      low = m1
    else:
      high = m2
  
  # print("res", low, high, (low + high) / 2.0)
  print(fun((low + high) / 2.0))
  pass

if __name__ == '__main__':
  # READ('in.txt')
  main()