from collections import Counter

s = input()

n = len(s)
F = [1 for _ in range(n + 1)]
for i in range(n):
    F[i + 1] = (i + 1) * F[i]

counter = Counter(s)
ans = F[n]
for cnt in counter.values():
    ans //= F[cnt]
print(ans - 1)