Problem 10: Angular Sweep (Diagonal Traverse) Problem Statement Given an m x n matrix mat, return an array of all the elements of the array in a diagonal order. Input Format A 2D integer matrix mat. Example Input: mat = [[1, 2, 3], [4, 5, 6], [7, 8, 9]] Output: [1, 2, 4, 7, 5, 3, 6, 8, 9]