Demo: https://basemax.github.io/ShapesAlgorithm/demo.html

In a shape(rectangle or square) with width n and length m, We want to know how many shapes there are with width and length a and b. We also want to know the remaining forms. For example, in the figure below, whose width and length are 10cm x 10cm, a shape with a width and length of 3 x 3 will be output as below:

• 9 items 3cm in 3cm (called G1)
• 3 items 1cm in 3cm (called G2)
• 3 items 3cm in 1cm (called G3)
• And a 1cm in 1cm item (called G4)

More about the problem: https://math.stackexchange.com/questions/4533522/how-to-calculate-number-of-shapes-inside-a-shape/4533998#4533998