Buggy python submission (verdict: Runtime Error):
import collections

N = int(input())
v = list(map(int,input().rstrip().split()))
list_odd = v[1::2]
list_even = v[0::2]

odd_count = collections.Counter(list_odd)
even_count = collections.Counter(list_even)


max_flq_odd = [kv for kv in odd_count.items() if kv[1] == max(odd_count.values())]
max_flq_even = [kv for kv in even_count.items() if kv[1] == max(even_count.values())]


if max_flq_odd[0][0] != max_flq_even[0][0] or len(max_flq_odd) > 1 or len(max_flq_even) > 1:
    #最大値のキーが違うものは最初にはじいた方が良い？
    print(N-max_flq_odd[0][1]-max_flq_even[0][1])
elif len(odd_count) == 1 and len(even_count) == 1:
    #数字が一種類しかない
    print(N//2)
elif len(odd_count) == 1:
    even_count.pop(max_flq_even[0][0])
    secondmax_even = max(even_count.values())
    print(N//2-secondmax_even)
elif len(even_count) == 1:
    odd_count.pop(max_flq_odd[0][0])
    secondmax_odd = max(odd_count.values())
    print(N//2-secondmax_odd)
else:
    even_count.pop(max_flq_even[0][0])
    secondmax_even = max(even_count.values())
    odd_count.pop(max_flq_odd[0][0])
    secondmax_odd = max(odd_count.values())
    print(min(N-max_flq_odd-secondmax_even, N-max_flq_even-secondmax_odd))

Fixed submission:
import collections

N = int(input())
v = list(map(int,input().rstrip().split()))
list_odd = v[0::2]
list_even = v[1::2]

odd_count = collections.Counter(list_odd).most_common()
even_count = collections.Counter(list_even).most_common()

if len(odd_count) == 1 and len(even_count) == 1:
    if odd_count[0][0] == even_count[0][0]:
        print(N//2)
    else:
        print(0)
elif odd_count[0][0] != even_count[0][0]:
    print(N-odd_count[0][1]-even_count[0][1])
elif len(odd_count) == 1:
    print(N//2-even_count[1][1])
elif len(even_count) == 1:
    print(N//2-odd_count[1][1])
else:
    print(min(N-odd_count[0][1]-even_count[1][1], N-even_count[0][1]-odd_count[1][1]))

Buggy python submission (verdict: Runtime Error):
import collections

N = int(input())
v = list(map(int,input().rstrip().split()))
list_odd = v[0::2]
list_even = v[1::2]

odd_count = collections.Counter(list_odd)
even_count = collections.Counter(list_even)


max_flq_odd = [kv for kv in odd_count.items() if kv[1] == max(odd_count.values())]
max_flq_even = [kv for kv in even_count.items() if kv[1] == max(even_count.values())]

if odd_count == even_count and len(odd_count) == 1:
    #数字が一種類しかない
    print(N//2)
elif max_flq_odd == max_flq_even and len(max_flq_odd) == 1:
    #最大値が同じで一種類しかない
    odd_wo_max = [kv for kv in odd_count if kv[1] != max(odd_count.values())]
    secondmax_odd = [kv for kv in odd_wo_max.items() if kv[1] == max(odd_wo_max.values())]
    even_wo_max = [kv for kv in odd_count if kv[1] != max(odd_count.values())]
    secondmax_even = [kv for kv in even_wo_max.items() if kv[1] == max(even_wo_max.values())]
    secondmax = max(secondmax_odd,secondmax_even)
    print(N-max_flq_odd-secondmax)
else:
    #最大値が違うか、最大値をとるキーが複数あり代替がきく
    print(N-max_flq_odd[0][1]-max_flq_even[0][1])

Fixed submission:
import collections

N = int(input())
v = list(map(int,input().rstrip().split()))
list_odd = v[0::2]
list_even = v[1::2]

odd_count = collections.Counter(list_odd).most_common()
even_count = collections.Counter(list_even).most_common()

if len(odd_count) == 1 and len(even_count) == 1:
    if odd_count[0][0] == even_count[0][0]:
        print(N//2)
    else:
        print(0)
elif odd_count[0][0] != even_count[0][0]:
    print(N-odd_count[0][1]-even_count[0][1])
elif len(odd_count) == 1:
    print(N//2-even_count[1][1])
elif len(even_count) == 1:
    print(N//2-odd_count[1][1])
else:
    print(min(N-odd_count[0][1]-even_count[1][1], N-even_count[0][1]-odd_count[1][1]))