useState counter logic

Easy 20 pts New · no attempts yet javascript

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Simulate useState: start at 0, increment twice, print final value.

Static hints

setState(s => s + 1) twice

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Official solution

let state = 0;
function setState(updater) {
  state = typeof updater === "function" ? updater(state) : updater;
}
setState(s => s + 1);
setState(s => s + 1);
console.log(state);

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Explanation

Functional updates avoid stale state—critical in async React interview answers.

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useState counter logic

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