from collections import defaultdict
S=input()
all=defaultdict(int)
for i in range(len(S)):
    all[S[i]]+=1
ans=0
left=defaultdict(int)
for i in range(len(S)):
    ans_d=left[S[i]]
    left[S[i]]+=1
    ans+=ans_d*(len(S)-1-i-(all[S[i]]-left[S[i]]))
print(ans)