import math
from collections import Counter 
S = input()

def nCr(n, r):
    f = math.factorial
    return f(n) // f(r) // f(n-r)

cnt = sorted(list(Counter(S).values()), reverse=True)

ans = 1
s = len(S)
for c in cnt:
    ans *= nCr(s, c)
    s -= c

print(ans-1)