'''
You have a stack of n boxes, with widths w_sub_i, heights h_sub_i, and depths d_sub_i. The boxes cannot be rotated and can only be stacked on top of one another if each box in the stack is strictly larger than the box above it in width, heigh, and depth. Implement a method to compute the height of the tallest possible stack. The height of a stack is the sum of the heights of each box.

Hints: 155, 194, 214, 260, 322, 368, 378
'''


def stack_of_boxes(s):
    pass

if __name__ == '__main__':
    assert stack_of_boxes('') ==
    assert stack_of_boxes('') ==
    assert stack_of_boxes('') ==
    assert stack_of_boxes('') ==
    assert stack_of_boxes('') ==
