Problem: A sequence a_1,a_2,... ,a_n is said to be /\/\/\/ when the following conditions are satisfied:    * For each i = 1,2,..., n-2, a_i = a_{i+2}.   * Exactly two different numbers appear in the sequence.  You are given a sequence v_1,v_2,...,v_n whose length is even. We would like to make this sequence /\/\/\/ by replacing some of its elements. Find the minimum number of elements that needs to be replaced.

Submission attempts (in order):
from collections import Counter


def main():
    n = int(input())
    v = list(map(int, input().split()))
    
    

    # a_count = Counter.most_common(Counter(a))
    # b_count = Counter.most_common(Counter(b))

    half_n = n // 2
    ac = Counter(v[::2]).most_common(2)
    bc = Counter(v[1::2]).most_common(2)

    if ac[0][0] != bc[0][0]:
        print(half_n - ac[0][1] - bc[0][1])
    else:
        if len(bc) == 1 or len(ac) == 1:
            print(half_n // 2)
        else:
            print(half_n - max(ac[0][1] + bc[1][1], ac[1][1] + bc[0][1]))

    # ans = 0

    # half_n = n // 2
    
    # h_ac0 = half_n - a_count[0][1]
    # h_bc0 = half_n - b_count[0][1]

    # if len(a_count) == 1 and len(b_count) == 1:
    #     if eq:
    #         print(half_n)
    #         exit()
    #     else:
    #         print(ans)
    #         exit()

    # if a_count[0][1] > b_count[0][1]:
    #     ans += h_ac0
    #     if eq:
    #         ans += half_n - b_count[1][1]
    #     else:
    #         ans += h_bc0
    # elif a_count[0][1] < b_count[0][1]:
    #     ans += h_bc0
    #     if eq:
    #         ans += half_n - a_count[1][1]
    #     else:
    #         ans += h_ac0
    # else:
    #     if eq:
    #         ans += h_ac0
    #         ans += half_n - b_count[1][1]
    #     else:
    #         ans += h_ac0
    #         ans += h_bc0
    # print(ans)


if __name__ == '__main__':
    main()


from collections import Counter


def main():
    n = int(input())
    v = list(map(int, input().split()))
    
    

    # a_count = Counter.most_common(Counter(a))
    # b_count = Counter.most_common(Counter(b))

    # half_n = n // 2
    ac = Counter(v[::2]).most_common(2)
    bc = Counter(v[1::2]).most_common(2)

    if ac[0][0] != bc[0][0]:
        print(n - ac[0][1] - bc[0][1])
    else:
        if len(bc) == 1 or len(ac) == 1:
            print(n // 2)
        else:
            print(n - max(ac[0][1] + bc[1][1], ac[1][1] + bc[0][1]))

    # ans = 0

    # half_n = n // 2
    
    # h_ac0 = half_n - a_count[0][1]
    # h_bc0 = half_n - b_count[0][1]

    # if len(a_count) == 1 and len(b_count) == 1:
    #     if eq:
    #         print(half_n)
    #         exit()
    #     else:
    #         print(ans)
    #         exit()

    # if a_count[0][1] > b_count[0][1]:
    #     ans += h_ac0
    #     if eq:
    #         ans += half_n - b_count[1][1]
    #     else:
    #         ans += h_bc0
    # elif a_count[0][1] < b_count[0][1]:
    #     ans += h_bc0
    #     if eq:
    #         ans += half_n - a_count[1][1]
    #     else:
    #         ans += h_ac0
    # else:
    #     if eq:
    #         ans += h_ac0
    #         ans += half_n - b_count[1][1]
    #     else:
    #         ans += h_ac0
    #         ans += h_bc0
    # print(ans)


if __name__ == '__main__':
    main()


Verdicts: Wrong Answer

Accepted