#!/usr/bin/env python

import functools
import sys


def solve(input: list[str]) -> int:
    def parse(input: list[str]) -> list[list[int]]:
        return [[int(c) for c in line] for line in input]

    def max_joltage(bank: list[int]) -> int:
        @functools.cache
        def recurse(bank: tuple[int, ...], length: int) -> int:
            assert length > 0  # Sanity check
            assert length <= len(bank)  # Sanity check
            if length == 1:
                return max(bank)
            return max(
                bank[i] * 10 ** (length - 1) + recurse(bank[i + 1 :], length - 1)
                for i in range(len(bank) - length + 1)
            )

        return recurse(tuple(bank), 12)

    batteries = parse(input)
    return sum(map(max_joltage, batteries))


def main() -> None:
    input = sys.stdin.read().splitlines()
    print(solve(input))


if __name__ == "__main__":
    main()