Training Grounds
Counter Never UpdatesWhite Belt
+10 Ki
Description

A counter displays a number and a button that increments it by one on each click.

Anomaly

Clicking the button does nothing - the number stays at 0 no matter how many times you click.

Constraint
Do not add useEffect or any other hook
Hint

Check what value you're actually passing to `setCount`.

Consult the SenseiOnly for those truly stuck · Flip to reveal

Check what value you're actually passing to `setCount`.

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Correct Solution
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Why this fixes it

`setCount(count)` passed the current value of `count` straight back into state - because React uses `Object.is` equality, it compared the new value against the old one, saw they were identical, and bailed out of the re-render entirely. Changing the argument to `count + 1` produces a value that is always different from the current state. React detects the new value, schedules a re-render, and the updated count appears on screen.

Expected OutputGoal State
Your OutputLive