How to count number of squares posible in a m*n grid.
I know formula to count squares which are parallel to given grid. i.e. m*(m+1)*(2m+1)/6 + (n-m)*m*(m+1)/2;
but how to do it for squares which are not parallel to given grid. How to count them??
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How to count number of squares posible in a m*n grid.
I know formula to count squares which are parallel to given grid. i.e. m*(m+1)*(2m+1)/6 + (n-m)*m*(m+1)/2;
but how to do it for squares which are not parallel to given grid. How to count them??
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Read your question again, slowly.
Errichto had a video where he solved a generalization of this problem on the spot: part (1) was count all axis-aligned rectangles formed by a given set of points, and part (2) was count all general rectangles (your problem asks for only squares, and the set of points is very regular). Nevertheless maybe you can gather some ideas from it:
https://youtu.be/EuPSibuIKIg?t=109
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