def solve(S):
  ans = 0
  ch = {c: 0 for c in "ABCDEFGHIJKLMNOPQRSTUVWXYZ"}
  N = len(S)
  for i in range(N):
    ch[S[i]] += 1
    if ch[S[i]] >= 2:
      ans += (ch[S[i]] - 1) * (N - i - 1)
  return ans

S = input()

print(solve(S))