Create a Counter — JavaScript

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準確率100%

已用時間0s

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字符數0

錯誤字符0

錯誤數0

進度0%

大寫鎖定已開啓

閱讀代碼練習指南

Use a closure to retain a private counter value.

function createCounter(start = 0) {
  let value = start;

  return () => {
    value += 1;
    return value;
  };
}

const next = createCounter(3);