def read_file(filename):
    """
    Read input file and save the crabs into a list.
    :param filename: input file
    :return: list of crabs
    """
    crabs = []
    with open(filename, 'r', encoding='UTF-8') as file:
        for line in file:
            for number in line.split(","):
                crabs.append(int(number))

    return crabs