## https://yukicoder.me/problems/no/2419



def main():
    S = input()

    dp = [0] * 52
    answer = 0
    for s in S:
        new_dp = dp.copy()
        x = ord(s) - ord("A")

        for j in range(26):
            if x != j:
                answer += dp[j + 26]

        new_dp[x + 26] += dp[x]
        new_dp[x] += 1
        dp = new_dp
    print(answer)





if __name__ == '__main__':
    main()