Problem p03713 (python)

Fixed submission:
n,m=list(map(int, input().split()))
lll = []
a = n
b = m
if (n * m) % 3 == 0:
    print(0)
else:
    for i in range(1, a):
        p = b * i

        if b % 2 == 1:
            q = (a - i) * (int(b / 2) + 1)
        elif b % 2 == 0:
            q = (a - i) * (int(b / 2))
        r = (a - i) * (int(b / 2))

        if (a - i) % 2 == 1:
            q2 = b * (int((a - i) / 2) + 1)
        elif (a - i) % 2 == 0:
            q2 = b * (int((a - i) / 2))

        r2 = b * (int((a - i) / 2))

        lll.append(min(max(p, q, r) - min(p, q, r), max(p, q2, r2) - min(p, q2, r2)))

    temp = b
    b = a
    a = temp
    for i in range(1, a):
        p = b * i

        if b % 2 == 1:
            q = (a - i) * (int(b / 2) + 1)
        elif b % 2 == 0:
            q = (a - i) * (int(b / 2))
        r = (a - i) * (int(b / 2))

        if (a - i) % 2 == 1:
            q2 = b * (int((a - i) / 2) + 1)
        elif (a - i) % 2 == 0:
            q2 = b * (int((a - i) / 2))

        r2 = b * (int((a - i) / 2))

        lll.append(min(max(p, q, r) - min(p, q, r), max(p, q2, r2) - min(p, q2, r2)))


    print(min(lll))

Buggy submission (verdict: Runtime Error):
n,m=list(map(int, input().split()))
lll = []
a = n
b = m
if (n * m) % 3 == 0:
    print(0)
else:
    for i in range(1, a):
        p = b * i

        if b % 2 == 1:
            q = (a - i) * (int(b / 2) + 1)
        elif b % 2 == 0:
            q = (a - i) * (int(b / 2))
        r = (a - i) * (int(b / 2))

        if a - i % 2 == 1:
            q2 = b * (int((a - i) / 2) + 1)
        elif (a - i) % 2 == 0:
            q2 = b * (int((a - i) / 2))

        r2 = b * (int((a - i) / 2))

        lll.append(min(max(p, q, r) - min(p, q, r), max(p, q2, r2) - min(p, q2, r2)))

    temp = b
    b = a
    a = temp
    for i in range(1, a):
        p = b * i

        if b % 2 == 1:
            q = (a - i) * (int(b / 2) + 1)
        elif b % 2 == 0:
            q = (a - i) * (int(b / 2))
        r = (a - i) * (int(b / 2))

        if a - i % 2 == 1:
            q2 = b * (int((a - i) / 2) + 1)
        elif (a - i) % 2 == 0:
            q2 = b * (int((a - i) / 2))

        r2 = b * (int((a - i) / 2))

        lll.append(min(max(p, q, r) - min(p, q, r), max(p, q2, r2) - min(p, q2, r2)))


    print(min(lll))

Buggy submission (verdict: Runtime Error):
n,m=list(map(int, input().split()))
lll = []
a = n
b = m
if (n * m) % 3 == 0:
    print(0)
else:
    for i in range(1, a):
        p = b * i
        
        if b % 2 == 1:
            q = (a - i) * (int(b / 2) + 1)
        elif b % 2 == 0:
            q = (a - i) * (int(b / 2))
        r = (a - i) * (int(b / 2))
        
        if a - i % 2 == 1:
            q2 = b * (int((a - i) / 2) + 1)
        elif (a- i) % 2 == 0:
            q2 = b * (int(a - i) / 2)

        r2 = b * (int(a - i) / 2)
        
        lll.append(min(max(p, q, r) - min(p, q, r), max(p, q2, r2) - min(p, q2, r2)))

    temp = b
    b = a
    a = temp
    for i in range(1, a):
        p = b * i

        if b % 2 == 1:
            q = (a - i) * (int(b / 2) + 1)
        elif b % 2 == 0:
            q = (a - i) * (int(b / 2))
        r = (a - i) * (int(b / 2))

        if a - i % 2 == 1:
            q2 = b * (int((a - i) / 2) + 1)
        elif (a - i) % 2 == 0:
            q2 = b * (int(a - i) / 2)

        r2 = b * (int(a - i) / 2)

        lll.append(min(max(p, q, r) - min(p, q, r), max(p, q2, r2) - min(p, q2, r2)))


    print(min(lll))