s = input()
dc = set((k for k in s))
c = 0
for _ in range(len(s)):
    t = s[0]
    s = s[1:]
    n = s.count(t) + 1
    if n > 1:
        n = s.index(t)
        k = s[n:]
        for i in dc:
            if i != t and i in k:
                c += k.count(i)
print(c)