S = input()
L = len(S)

chars = set(S)

#print(chars)

D:dict[str,list[int]] = dict()
for c in chars:
    D[c] = []

#print(D)

for i in range(L):
    D[S[i]].append(i) 

#print(D)

ans = 0

for c in chars:
    if c not in D or len(D[c]) == 1:continue
    else:
        #print(c,D[c])
        A = D[c]
        N = len(A)
        for i in range(1,N):
            #print(f"{i=},{A[i]=},{L=}")
            ans += i * (L-A[i]-(N-i))
        #print(f"{ans=}")

print(ans)