def sort_and_count_inversions(seq):
"""Sort a sequence and count inversions.

Argument: seq -- a sequence

Result: number of inversions (cases where i < j, but seq[i] > seq[j]).

Side effect: seq is sorted.

"""
def sort_and_count(seq, start, end):
    if end - start < 2:
        return 0
    middle = (start + end) // 2
    return (sort_and_count(seq, start, middle)
            + sort_and_count(seq, middle, end)
            + merge_and_count_inversions(seq, start, middle, end))
return sort_and_count(seq, 0, len(seq))

tabela = input()
array = list(tabela)
print (sort_and_count_inversions(array))