def get_square_indices(row, col):
    """
    Given row and col of a cell, find all adjacent cells in its square.
    Return a list of zero-based indices
    """
    sq_row, sq_col = row/3, col/3
    # Identify the start location of square index in the grid
    sq_start_ndx = (sq_row*9*3) + (sq_col*3)
    sq_indices = [sq_start_ndx+c for c in [0, 1, 2, 9, 10, 11, 18, 19, 20]]

    return sq_indices