mouth

c d

Suppose this is the front view of a 3*3*3 cube, make a cross section from A to B, and only take the squares where the cross section passes, then the left view and the top view are all 3*3 squares, take three squares from A to D and turn 90 degrees. At this time, the left view and the top view have not changed, and the front view becomes a diagonal line, and then four squares are added, so that the front view has 3*3 squares, so the total * *.

I wonder if there is a smaller one:)