Problem p03244 (python)

Fixed submission:
from collections import Counter
n = int(input())
a = [int(i) for i in input().split()]

if len(set(a)) == 1:
    p = int(n/2)
else:
    b0 = set(a[::2])
    if len(b0)==1:
        q0 = 0
        mark00 = a[0]
        count00, count01 = int(n/2), 0
    else:
        c = Counter(a[::2])
        q0 =  int(n/2) - c.most_common(1)[0][1]
        mark00, mark01 = c.most_common(2)[0][0], c.most_common(2)[1][0]
        count00, count01 = c.most_common(2)[0][1], c.most_common(2)[1][1]

    b1 = set(a[1::2])
    if len(b1)==1:
        q1 = 0
        mark10 = a[1]
        count10, count11 = int(n/2), 0
    else:
        c = Counter(a[1::2])
        q1 =  int(n/2) - c.most_common(1)[0][1]
        mark10, mark11 = c.most_common(2)[0][0], c.most_common(2)[1][0]
        count10, count11 = c.most_common(2)[0][1], c.most_common(2)[1][1]
    if mark00==mark10:
        if count00+count01>count10+count11:
            p = n - (count00+count01)
        else:
            p = n - (count10+count11)
    else:
        p = n - (count00 + count10)

print(p)

Buggy submission (verdict: Runtime Error):
from collections import Counter
n = int(input())
a = [int(i) for i in input().split()]

if len(set(a)) == 1:
    p = int(n/2)
else:
    b0 = set(a[::2])
    if len(b0)==1:
        q0 = 0
        mark00 = a[0]
        count00, count01 = n/2, 0
    else:
        c = Counter(l)
        q0 =  int(n/2) - c.most_common(1)[0][1]
        mark00, mark01 = c.most_common(2)[0][0], c.most_common(2)[1][0]
        count00, count01 = c.most_common(2)[0][1], c.most_common(2)[1][1]

    b1 = set(a[1::2])
    if len(b1)==1:
        q1 = 0
        mark10 = a[1]
        count10, count11 = n/2, 0
    else:
        c = Counter(l)
        q1 =  int(n/2) - c.most_common(1)[0][1]
        mark10, mark11 = c.most_common(2)[0][0], c.most_common(2)[1][0]
        count10, count11 = c.most_common(2)[0][1], c.most_common(2)[1][1]
    if mark00==mark10:
        if count00+count01>count10+count11:
            p = n - (count00+count01)
        else:
            p = n - (count10+count11)
    else:
        p = n - (count00 + count10)

print(p)

Buggy submission (verdict: Runtime Error):
from collections import Counter
n = int(input())
a = [int(i) for i in input().split()]

if len(set(a)) == 1:
    p = int(n/2)
else:
    b0 = set(a[::2])
    if len(b0)==1:
        q0 = 0
        mark00 = b0[0]
        count00, count01 = n/2, 0
    else:
        c = Counter(l)
        q0 =  int(n/2) - c.most_common(1)[0][1]
        mark00, mark01 = c.most_common(2)[0][0], c.most_common(2)[1][0]
        count00, count01 = c.most_common(2)[0][1], c.most_common(2)[1][1]

    b1 = set(a[1::2])
    if len(b1)==1:
        q1 = 0
        mark10 = b1[0]
        count10, count11 = n/2, 0
    else:
        c = Counter(l)
        q1 =  int(n/2) - c.most_common(1)[0][1]
        mark10, mark11 = c.most_common(2)[0][0], c.most_common(2)[1][0]
        count10, count11 = c.most_common(2)[0][1], c.most_common(2)[1][1]
    if mark00==mark10:
        if count00+count01>count10+count11:
            p = n - (count00+count01)
        else:
            p = n - (count10+count11)
    else:
        p = n - (count00 + count10)

print(p)