🧒 Explain like I'm 5
Imagine you have a traffic light with three colors: red, yellow, and green. You need to make sure that once it turns red, it never goes back to green directly. Similarly, in programming, you can have a variable that can be in three states, and you need to control how it changes between these states.
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Senior-level deep dive: internals, pitfalls, and a self-interview ladder.
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