S = input().strip()
N = len(S)
count = 0

for i in range(N):
    for j in range(i+1, N):
        for k in range(j+1, N):
            for l in range(k+1, N):
                for m in range(l+1, N):
                    a, b, c, d, e = S[i], S[j], S[k], S[l], S[m]
                    if a == c and len({a, b, d, e}) == 4:
                        count += 1

print(count)