2097. Valid Arrangement of Pairs

You are given a 0-indexed 2D integer array pairs where pairs[i] = [starti, endi]. An arrangement of pairs is valid if for every index i where 1 <= i < pairs.length, we have endi-1 == starti. Return any valid arrangement of pairs. Note: The inputs will be generated such that there exists a valid arrangement of pairs. Example 1: Input: pairs = [[5,1],[4,5],[11,9],[9,4]] Output: [[11,9],[9,4],[