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import sys
from collections import deque
from math import gcd

n = int(input())
a = list(map(int,sys.stdin.readline().split()))

###

small_primes = [2,3,5,7,11,13,17,19,23,29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241]
def is_prime_fast(n):
  """
  (1) Tests primality of n
  (2) uses trial division < 200,000
  (2) >= 200,000 : Miller-Rabin w/ preselected bases up to 3317044064679887385961980 (~3 * 10^24)
  """
  if n < 200000:
    if n <= 1: return False
    if n ==2 or n ==3: return True
    if n % 2 == 0 or n % 3 == 0: return False
    k = 5
    while k*k <= n:
      if n % k == 0 or n % (k+2) == 0: return False
      k += 6
    return True
  elif n < 1373653:
    bases = [2,3]
  elif n < 25326001:
    bases = [2,3,5]
  elif n < 3215031751:
    bases = [2,3,5,7]
  elif n < 2152302898747:
    bases = [2,3,5,7,11]
  elif n < 3474749660383:
    bases = [2,3,5,7,11,13]
  elif n < 341550071728321:
    bases = [2,3,5,7,11,13, 17]
  elif n < 3825123056546413051:
    bases = [2,3,5,7,11,13, 17, 19, 23]
  elif n < 318665857834031151167461:
    bases = [2,3,5,7,11,13, 17, 19, 23, 29, 31, 37]
  elif n < 3317044064679887385961981:
    bases = [2,3,5,7,11,13, 17, 19, 23, 29, 31, 37, 41]
  else:
    raise ValueError(f"{n} is too large for Miller-Rabin with these bases!")

  for sp in small_primes:
    if n % sp == 0: return False  
  s = 0
  multiplier = 1
  while (n-1) % (multiplier*2) == 0:
    multiplier *= 2
    s += 1
  d = (n-1) // multiplier
  for base in bases:
    if pow(base, d, n) == 1:
      continue
    multiplier = 1
    spp = False
    for r in range(s):
      if pow(base, (2 ** r) * d , n) == n-1:
        spp = True
        break
    if not spp: return False
  return True

def get_divisor_pollard_rho(n):
  """
  (1) Returns factor of n
  (2) Requires n not be prime
  """
  if n % 2 == 0: return 2
  if n % 5 == 0: return 5
  def g(z):
    return (z**2 + 1) % n
  for b in range(2, n):
    x, y = b, b
    d = 1
    while d == 1: 
      x = g(x)
      y = g(g(y))
      d = gcd(abs(x-y), n)

    if d != n:
      return d

def get_prime_factorization_from_pfwm(pfwm):
  """Given prime factorization with multiplicity, return pf = [(prime, power), ...]"""
  pf = []
  k = 0
  while k < len(pfwm):
    prime = pfwm[k]
    power = 1
    while k+1 < len(pfwm) and pfwm[k+1] == prime:
      power += 1
      k += 1
    pf.append((prime, power))
    k += 1
  return pf

def get_prime_factorization_with_multiplicity(n, is_prime=is_prime_fast, get_divisor=get_divisor_pollard_rho):
  """
  (1) Returns list of prime factors with multiplicity for n 
  (2) Requires is_prime and get_divisor functions (presumably Miller-Rabin and Pollard's Rho)  
  """
  def f(n):
    if n == 1:
      return []
    if is_prime(n):
      return [n]
    d = get_divisor(n)
    return f(d) + f(n // d)
  return f(n)


def get_prime_factorization(n, is_prime=is_prime_fast, get_divisor=get_divisor_pollard_rho):
  """Given n, with optional is_prime(), get_divisor(), return prime_factorization = [(prime, power), ...] of n"""
  return get_prime_factorization_from_pfwm(sorted(get_prime_factorization_with_multiplicity(n, is_prime, get_divisor)))

def get_normal_factors_pf(pf):
  """Given pf = [(prime, power), ...], return all factors in normal form, i.e., integers"""  
  if not pf:
    return [1]
  n = 1
  for _, e in pf:
    n *= (e+1)
  factors = [0] * n
  factors[0] = 1
  j = 1
  for p, e in pf:
    flen, ppow = j, 1
    for _ in range(e):
      ppow *= p
      for i in range(flen):
        factors[j] = factors[i]*ppow
        j += 1
  return factors

###


def try_k(k):
  q, total = deque(), 0

  for i in range(n):
    if len(q) >= k:
      total -= q.popleft()
    # print(f"{i=} {q=} {total=}")
    if total > a[i]: 
      # print(f"hit too much condition with {i=} {q=}")
      return False
    delta = a[i] - total
    if delta and i + k - 1 >= n:
      return False
    q.append(delta)
    total += delta
    # print(f"  {delta=}")
  return True

s = sum(a)
pf_s = get_prime_factorization(s)
fs = get_normal_factors_pf(pf_s)
fs_filtered = []
for f in fs:
  if f <= n: fs_filtered.append(f)
fs_filtered.sort()
# print(s, pf_s, fs)

for cand_k in range(len(fs_filtered)-1, -1, -1):
  if try_k(cand_k):
    print(cand_k)
    break