Question 18
As shown in the following figure, there are four types of blocks formed by four cubes of side one. How many ways are there for putting four blocks of these types in a $2 \times 2 \times 4$ rectangular box so that they do not stick out?
Note that we can use multiple blocks of the same type, and blocks can be rotated. Additionally, we distinguish ways which coincide with each other by rotating the box.
Note that we can use multiple blocks of the same type, and blocks can be rotated. Additionally, we distinguish ways which coincide with each other by rotating the box.