# alphabet countsリストを作るか
# そのときのアルファベットのコンボ数を引いた数をansに加算

alphabets = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
dic = {}
for i in range(26):
    dic[alphabets[i]] = i
    
alphabet_counts = [0]*26
combo_sum = 0

S = input()
N = len(S)

ans = 0
for i in range(N):
    s = S[i]
    old = alphabet_counts[dic[s]]
    alphabet_counts[dic[s]] += 1
    combo_sum -= (old-1)*(old)//2
    ans += combo_sum
    combo_sum += (old)*(old+1)//2
    #print('i', i, 'alphabet_counts', alphabet_counts)
    #print('combo_sum', combo_sum, 'ans', ans)
    
print(ans)