sleep-sort.js

function sleepSort(numbers) {
  const sorted = [];
  
  return new Promise((resolve) => {
    numbers.forEach(num => setTimeout(() => {
      sorted.push(num);
      
      // resolve promise when all numbers have been pushed.
      if (sorted.length === numbers.length) {
        resolve(sorted);
      }
    }, num));
  });
}

sleepSort([8, 42, 38, 111, 2, 39, 1]).then(sorted => console.log(sorted));

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