Description
Given an m x n matrix, return all elements in diagonal order. Start from top-left, traverse diagonally alternating between up-right and down-left directions.
Examples
Input:
mat = [[1,2,3],[4,5,6],[7,8,9]]Output:
[1,2,4,7,5,3,6,8,9]Explanation:
Traverse diagonally alternating directions.
Input:
mat = [[1,2,3,4]]Output:
[1,2,3,4]Explanation:
For a single row matrix, diagonal traversal simply goes from left to right across the row, as each element forms its own diagonal.
Input:
mat = [[1],[2],[3]]Output:
[1,2,3]Explanation:
For a single column matrix, diagonal traversal goes from top to bottom down the column, as each element forms its own diagonal going in the downward direction.
Constraints
- •
1 ≤ m, n ≤ 100