As an interviewer I've seen candidates immediately recognize my interview question (let's be honest, with Leetcode unless you invest time to keep crafting new q

As an interviewer I've seen candidates immediately recognize my interview question (let's be honest, with Leetcode unless you invest time to keep crafting new questions, sooner or later it gets leaked). The interesting part is that you can still get enough signal to tell who understood the solution vs who only memorized it. (e.g. in my question you had to do a pre-processing to transform it into a classical question on leetcode; people who only memorized the solution wouldn't even recognize that and would find the input does not "fit" into the canned solution)