from itertools import combinations

def count_cpctf_like_subsequences(S):
    N = len(S)
    count = 0
    for i, j, k, l, m in combinations(range(N), 5):
        s1, s2, s3, s4, s5 = S[i], S[j], S[k], S[l], S[m]
        if s1 == s3:
            if len(set([s1, s2, s4, s5])) == 4:
                # s1とs3が同じで、他が全て異なれば条件を満たす
                count += 1
    return count