Diagonal Traverse · Interview Problem

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Leetcode

Medium

Matrices

Arrays

Simulation

Diagonal Traverse

Return all elements of a matrix in diagonal order, alternating direction on each diagonal.

Acceptance 0%

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Problem Statement

Given an $m \times n$ matrix, visit every element exactly once and return the values in the order of a diagonal zigzag traversal.

Start from the top-left cell. For each diagonal, alternate between moving up-right and down-left. When the traversal reaches a boundary, move to the next valid starting cell for the following diagonal.

Your task is to produce the sequence of visited values.

Input Format

A 2D integer matrix mat with m rows and n columns.
The matrix may be rectangular, not necessarily square.

Output Format

Return an array containing the matrix elements in diagonal traversal order.

Constraints

$1 \le m, n$
All matrix elements are integers.
Visit each cell exactly once.

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