Problem p03061 (python)

Fixed submission:
from fractions import gcd

n = int(input())
a = list(map(int, raw_input().split()))

forward = []
backward = [0 for x in range(n)]

if n == 2:
    print(max(a[0], a[1]))
    exit(0)

for i in range(n):
    if i == 0:
        forward.append(a[i])
    else:
        forward.append(gcd(forward[i - 1], a[i]))


for i in range(n - 1, -1, -1):
    if i == n - 1:
        backward[i] = a[i]
    else:
        backward[i] = gcd(backward[i + 1], a[i])


ans = 1

for i in range(n):
    if i == 0:
        ans = max(ans, backward[1])
    elif i == n - 1:
        ans = max(ans, forward[n - 2])
    else:
        ans = max(ans, gcd(forward[i - 1], backward[i + 1]))

print(ans)

Buggy submission (verdict: Runtime Error):
from math import gcd

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

forward = []
backward = [0 for x in range(n)]

if n == 2:
    print(max(a[0], a[1]))
    exit(0)

for i in range(n):
    if i == 0:
        forward.append(a[i])
    else:
        forward.append(gcd(forward[i - 1], a[i]))


for i in range(n - 1, -1, -1):
    if i == n - 1:
        backward[i] = a[i]
    else:
        backward[i] = gcd(backward[i + 1], a[i])


ans = 1

for i in range(n):
    if i == 0:
        ans = max(ans, backward[1])
    elif i == n - 1:
        ans = max(ans, forward[n - 2])
    else:
        ans = max(ans, gcd(forward[i - 1], backward[i + 1]))

print(ans)

Buggy submission (verdict: Runtime Error):
from fractions import gcd

n = int(input())
a = list(map(int, raw_input().split()))

forward = []
backward = [0 for x in range(n)]

if n == 2:
    print(max(a[0], a[1]))
    exit(0)

for i in range(n):
    if i == 0:
        forward.append(a[i])
    else:
        forward.append(gcd(forward[i - 1], a[i]))


for i in range(n - 1, -1, -1):
    if i == n - 1:
        backward[i] = a[i]
    else:
        backward[i] = gcd(backward[i + 1], a[i])


ans = 1

for i in range(n):
    if i == 0:
        ans = max(ans, backward[1])
    elif i == n - 1:
        ans = max(ans, forward[n - 2])
    else:
        ans = max(ans, gcd(forward[i - 1], backward[i + 1]))

print(ans)

Buggy submission (verdict: Runtime Error):
from fractions import gcd

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

forward = []
backward = [0 for x in range(n)]

if n == 2:
    print(max(a[0], a[1]))
    exit(0)

for i in range(n):
    if i == 0:
        forward.append(a[i])
    else:
        forward.append(gcd(forward[i - 1], a[i]))


for i in range(n - 1, -1, -1):
    if i == n - 1:
        backward[i] = a[i]
    else:
        backward[i] = gcd(backward[i + 1], a[i])


ans = 1

for i in range(n):
    if i == 0:
        ans = max(ans, backward[1])
    elif i == n - 1:
        ans = max(ans, forward[n - 2])
    else:
        ans = max(ans, gcd(forward[i - 1], backward[i + 1]))

print ans

Buggy submission (verdict: Runtime Error):
from fractions import gcd

n = int(input())
a = list(map(int, raw_input().split()))

forward = []
backward = [0 for x in range(n)]

if n == 2:
    print(max(a[0], a[1]))
    exit(0)

for i in range(n):
    if i == 0:
        forward.append(a[i])
    else:
        forward.append(gcd(forward[i - 1], a[i]))


for i in range(n - 1, -1, -1):
    if i == n - 1:
        backward[i] = a[i]
    else:
        backward[i] = gcd(backward[i + 1], a[i])


ans = 1

for i in range(n):
    if i == 0:
        ans = max(ans, backward[1])
    elif i == n - 1:
        ans = max(ans, forward[n - 2])
    else:
        ans = max(ans, gcd(forward[i - 1], backward[i + 1]))

print ans