def get_neighbors(r_index, c_index):
    """Get neighboring cell positions

    Args:
        r_index (int): Current row index
        c_index ([type]): Current column index

    Returns:
        [List of list of integers]: List of neighbors with each neighbor containing a list of their row and column index.
    """
    neighbors = []
    for x in range(-1, 2, 1):
        for y in range(-1, 2, 1):
            if x != 0 or y != 0:
                neighbors.append([r_index + x, c_index + y])
    return neighbors