I recently came across a claim about binary trees that I was unable to prove. Given a binary tree, $$$\sum{|child_l|\times |child_r| } = O(N^2)$$$
Could someone provide proof and/or a way to intuitively explain this?
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Proving certain binary tree property
I recently came across a claim about binary trees that I was unable to prove. Given a binary tree, $$$\sum{|child_l|\times |child_r| } = O(N^2)$$$
Could someone provide proof and/or a way to intuitively explain this?
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