There is a React component with a counter (useState), a button that increments the counter by 1, and a list of 100 items. What happens when the button is clicked?
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Have you had experience with memory leaks? How did you find and fix them?
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What happens to the DOM tree when the state is updated in React?
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What are the goals of using the useRef hook?
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There is a component with a counter that should increase every second using setInterval, but it doesn't work correctly. How to fix it?
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Tell us about yourself, your main experience, achievements, and key tasks you have performed.
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Do you have experience using Set and Map? In what cases did you choose them?
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Is it necessary to use useMemo for primitive data types when passing to a child component?
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When running a project, errors occur — the Node.js version does not match. How would you handle this problem?
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What is the complexity of searching for an element in a Set compared to an array?
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There is a heavy CSS bundle of 2 megabytes. What can be done with it to unload rendering and make page building smooth?
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How much time did it take to write tests compared to regular work?
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How would you type a function in TypeScript that takes an array of any data types and returns the type of the first element?
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How did you work with AI when writing tests?
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Why does useCallback help avoid unnecessary re-renders when passing a function to a child component?
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How does React.memo check if it needs to update a component? How does it compare props?
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