1
var sequentialDigits = function (low, high) {
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  const digits = "123456789";
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  const ans = [];
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  const minLen = low.toString().length;
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  const maxLen = high.toString().length;
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  for (let windowSize = minLen; windowSize <= maxLen; ++windowSize) {
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    for (let i = 0; i + windowSize <= digits.length; ++i) {
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      const num = parseInt(digits.substring(i, i + windowSize));
11

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      if (num >= low && num <= high) {
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        ans.push(num);
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      }
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    }
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  }
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  return ans;
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};