Medium data structure and algorithm practice puzzle.
Given two binary trees, return true only if they have the same shape and the same values in the same places. Compare them together. If both nodes are empty, that's a match. If only one is, it's not. Otherwise, the values have to match, and then both left subtrees and both right subtrees have to match.
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 Event Taxonomy Builder, a pipeline you can run and download. See every Software Engineer project.
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