give root binary tree find maximum value v exist different node b v aval bval ancestor ba node ancestor b child equal b child ancestor b Example 1input root 831016null14nullnull4713output 7explanation we ancestornode difference give 8 3 53 7 48 1 710 13 3among possible difference maximum value 7 obtain 8 1 7example 2input root 1null2null03Output 3 ConstraintsThe number nod tree range 2 50000 Nodeval 105