import sys
import typing


def main() -> int:
    counts_sum = sum([c for c in _iter_group_counts(sys.stdin)])
    print(f"counts_sum={counts_sum}")

    return 0


def _iter_group_counts(instream: typing.TextIO) -> typing.Generator[int, None, None]:
    cur_group = set()
    for line in instream:
        line = line.strip()
        if line == "":
            yield len(cur_group)
            cur_group = set()
        for c in list(line):
            cur_group.add(c)

    yield len(cur_group)


if __name__ == "__main__":
    sys.exit(main())