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Elementary school mathematics building blocks
The first building block has five choices: choose not to choose, choose 1, 2, 3, 4, * * *;

There are four choices for the second building block: choose not to choose, choose 1, 2, 3, * * *;

There are four choices for the third building block: select or not, select 1, 2,3 and * * *.

Therefore, the total number of selections is

5×4×4=80 (species)

But among them, choosing none is not up to the requirements.

So, * * * has.

80- 1=79 (type)