Medium data structure and algorithm practice puzzle.
Given an array and k, shift every item k places to the right, with items that fall off the end wrapping around to the front. So [1, 2, 3, 4, 5] rotated by 2 is [4, 5, 1, 2, 3]. Take k mod the length first, since rotating by the full length changes nothing. Then the answer is the last k items followed by the rest.
Solve it three ways: snap the jigsaw pieces together, fill in the blanks, or type it from scratch against the tests. This one is free.
Every line of the solution comes with a note explaining why it is there, and a step by step replay shows the code running. At level 3, where you type it yourself, you can ask for an AI mock interview on this problem that ends with a hiring manager's scorecard.
Then grow it into a real project with the Software Engineer button: this puzzle becomes the Frame Audit Trail, a pipeline you can run and download. See every Software Engineer project.
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