Find root of the tree where children id sum for every node is given
Given a Binary Tree with nodes labelled from 1 to n, where n is the total number of nodes. The task is to identify the root of binary tree given that each node is described by a pair consisting of its id and the sum of its children's id's. Examples: Input: [[1, 5], [2, 0], [3, 0], [4, 0], [5, 5], [6