def compute_leading_dashes_y(alignment, ind_x, seq_x, seq_y, scoring_matrix, alignment_matrix):
    """ int, str, str, int, str, str, dict of dict, list of list -> int, str, str, int, int
    Helper function that takes the current alignment strings and score and then
    computes the next pair in the alignment with the remaining values in the y
    alignment string being dashes.  Returns the current position in seq_x and
    seq_y as well as the current score and alignment strings.
    """
    alignment[1] = seq_x[ind_x - 1] + alignment[1]
    alignment[2] = '-' + alignment[2]
    ind_x -= 1
    alignment[0] += scoring_matrix[alignment[1][0]][alignment[2][0]]

    return alignment[0], alignment[1], alignment[2], ind_x