import sys
input=lambda: sys.stdin.readline().rstrip()
import collections
S=list(input())
n=len(S)
S=collections.Counter(S)
F=[1]
for i in range(1,n+1):
  F.append(F[-1]*i)
ans=F[-1]
for i in S.values():
  ans//=F[i]
print(ans-1)