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Five short questions a day, picked from what you haven't seen yet. Built for the two weeks before a technical interview.

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SAMPLE · OUTPUT PREDICTION00:42

What does this log when the button is clicked twice?

source
const [n, setN] = useState(0);
function onClick() {
  setN(n + 1);
  setN(n + 1);
  console.log(n);
}
stdout
A0 then 0
B0 then 1
C1 then 2
D2 then 2