Hard data structure and algorithm practice puzzle.
Given a sorted array that's been rotated, like [3, 4, 5, 1, 2], return its smallest value. Compare the middle with the RIGHT end. If the middle is bigger, the drop is somewhere to the right, so search there. Otherwise, the smallest is at mid or to its left.
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 Reading Quantile Rig, a pipeline you can run and download. See every Software Engineer project.
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