Buggy python submission (verdict: Time Limit Exceeded):
N = int(input())
numbers = list(map(int, input().split()))

def gcd(a, b):
  remainder = a % b
  while (remainder > 0):
    a = b
    b = remainder
    remainder = a % b
  return b

gcd_forward = []
gcd_all = numbers[0]
for i in range(0, N - 1):
  gcd_all = gcd(gcd_all, numbers[i])
  gcd_forward.append(gcd_all)

gcd_backward = []
gcd_all = numbers[-1]
for i in range(N - 1, 0, -1):
  gcd_all = gcd(gcd_all, numbers[i])
  gcd_backward.insert(0, gcd_all)

gcd_forward.insert(0, gcd_backward[0])
gcd_backward.append(gcd_forward[-1])

gcd_max = 1
for i in range(N):
  gcd_max = max(gcd_max, gcd(gcd_forward[i], gcd_backward[i]))
  
print(gcd_max)


Fixed submission:
N = int(input())
numbers = list(map(int, input().split()))

def gcd(a, b):
  r = a % b
  while (r > 0):
    a = b
    b = r
    r = a % b
  return b

gcd_forward = [numbers[0]]
for i in range(1, N - 1):
  gcd_all = gcd(gcd_forward[-1], numbers[i])
  gcd_forward.append(gcd_all)

gcd_backward = [numbers[-1]]
for i in range(N - 2, 0, -1):
  gcd_all = gcd(gcd_backward[-1], numbers[i])
  gcd_backward.append(gcd_all)

gcd_max = 1
for i in range(N):
  gcd_temp = 1
  if (i == 0):
    gcd_temp = gcd_backward[-1]
  elif (i == N - 1):
    gcd_temp = gcd_forward[-1]
  else:
    gcd_temp = gcd(gcd_forward[i - 1], gcd_backward[N - 2 - i])
  gcd_max = max(gcd_max, gcd_temp)
  
print(gcd_max)

Buggy python submission (verdict: Time Limit Exceeded):
N = int(input())
numbers = list(map(int, input().split()))

def gcd(a, b):
  if (min(a, b) == 0):
    return max(a, b)
  elif (a > b):
    return gcd(b, a % b)
  else:
    return gcd(a, b % a)

gcd_forward = []
gcd_all = numbers[0]
for i in range(0, N - 1):
  if (gcd_all > 1):
    gcd_all = gcd(gcd_all, numbers[i])
  gcd_forward.append(gcd_all)

gcd_backward = []
gcd_all = numbers[-1]
for i in range(N - 1, 0, -1):
  if (gcd_all > 1):
    gcd_all = gcd(gcd_all, numbers[i])
  gcd_backward.insert(0, gcd_all)

gcd_forward.insert(0, gcd_backward[0])
gcd_backward.append(gcd_forward[-1])

gcd_max = 1
for i in range(N):
  if (gcd_forward[i] > 1 and gcd_backward[i] > 1):
    gcd_max = max(gcd_max, gcd(gcd_forward[i], gcd_backward[i]))
  
print(gcd_max)


Fixed submission:
N = int(input())
numbers = list(map(int, input().split()))

def gcd(a, b):
  r = a % b
  while (r > 0):
    a = b
    b = r
    r = a % b
  return b

gcd_forward = [numbers[0]]
for i in range(1, N - 1):
  gcd_all = gcd(gcd_forward[-1], numbers[i])
  gcd_forward.append(gcd_all)

gcd_backward = [numbers[-1]]
for i in range(N - 2, 0, -1):
  gcd_all = gcd(gcd_backward[-1], numbers[i])
  gcd_backward.append(gcd_all)

gcd_max = 1
for i in range(N):
  gcd_temp = 1
  if (i == 0):
    gcd_temp = gcd_backward[-1]
  elif (i == N - 1):
    gcd_temp = gcd_forward[-1]
  else:
    gcd_temp = gcd(gcd_forward[i - 1], gcd_backward[N - 2 - i])
  gcd_max = max(gcd_max, gcd_temp)
  
print(gcd_max)

Buggy python submission (verdict: Time Limit Exceeded):
N = int(input())
numbers = list(map(int, input().split()))

def gcd(a, b):
  if (min(a, b) == 0):
    return max(a, b)
  elif (a > b):
    return gcd(b, a % b)
  else:
    return gcd(a, b % a)

gcd_forward = []
gcd_all = numbers[0]
for i in range(0, N - 1):
  gcd_all = gcd(gcd_all, numbers[i])
  gcd_forward.append(gcd_all)

gcd_backward = []
gcd_all = numbers[-1]
for i in range(N - 1, 0, -1):
  gcd_all = gcd(gcd_all, numbers[i])
  gcd_backward.insert(0, gcd_all)

gcd_forward.insert(0, gcd_backward[0])
gcd_backward.append(gcd_forward[-1])

gcd_max = 1
for i in range(N):
  gcd_max = max(gcd_max, gcd(gcd_forward[i], gcd_backward[i]))
  
print(gcd_max)


Fixed submission:
N = int(input())
numbers = list(map(int, input().split()))

def gcd(a, b):
  r = a % b
  while (r > 0):
    a = b
    b = r
    r = a % b
  return b

gcd_forward = [numbers[0]]
for i in range(1, N - 1):
  gcd_all = gcd(gcd_forward[-1], numbers[i])
  gcd_forward.append(gcd_all)

gcd_backward = [numbers[-1]]
for i in range(N - 2, 0, -1):
  gcd_all = gcd(gcd_backward[-1], numbers[i])
  gcd_backward.append(gcd_all)

gcd_max = 1
for i in range(N):
  gcd_temp = 1
  if (i == 0):
    gcd_temp = gcd_backward[-1]
  elif (i == N - 1):
    gcd_temp = gcd_forward[-1]
  else:
    gcd_temp = gcd(gcd_forward[i - 1], gcd_backward[N - 2 - i])
  gcd_max = max(gcd_max, gcd_temp)
  
print(gcd_max)