Failing a technical interview is almost impossible. But, there is one mistake you can make that will almost certainly knock you out of the running: completing a problem without testing your code on any test cases.

While it's important to simply have test cases to avoid failing the interview, it's also crucial to select the right test cases. Our CEO, Sophie, gives her insight on what makes a good test case and shares a set of rules that you can use to identify them on your own.

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