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There is a cuboid with a dimension of $3\times4\times5$. Now paint all the surfaces red and cut it into many $1\times1\times1$ cubes. How many cubes that have two faces painted red are there? 
Overseas Competition->Knowledge Point->Counting Modules->Law of Addition and Multiplication->Coloring Problems
Remove the two cubes in both ends, and then we can get: $[(3-2)+(4-2)+(5-2)]\times4=24$ 