learn-co-curriculum / phase-5-practice-challenge-diagonal-traverse

Phase 5 Practice Challenge: Diagonal Traverse

In this practice challenge, you will get an opportunity to use the Data Structures and Algorithms skills you have built over the course of the program. It will also help you prepare for the types of challenges you can expect to see in job interviews.

Instructions

Create a method #diagonal_traverse that takes a matrix (a nested array) as input and returns a new array containing the elements in "diagonal" order.

Your method should start the traversal in the upper left corner (matrix[0][0]) and continue as indicated by the arrows. For the example above, the order of traversal would be: 1 => 2 => 4 => 7 => 5 => 3 => 6 => 8 => 9.

Other Examples:

diagonal_traverse([[1, 2], [3, 4]])
# => [1, 2, 3, 4]

diagonal_traverse([[1, 2], [3, 4], [5, 6]])
# => [1, 2, 3, 5, 4, 6]

diagonal_traverse([[1], [2], [3]])
# => [1, 2, 3]

Remember the process:

1. Rewrite the problem in your own words
2. Write your own test cases
3. Pseudocode
4. Code
5. Refactor to make it clean and readable
6. Refactor to optimize

Once you have a complete solution, run the test suite using learn test as a final check.

Check Out the Solution

Several possible approaches for completing this challenge are provided in a separate lesson. Once your code is working and you have all the tests passing, be sure to take a look at the example solutions provided. This will give you exposure to different approaches for solving this challenge, and may also give you ideas for how you might want to refactor your code to make it better.