First Bad Version LeetCode solution in JavaScript

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/**
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 * Definition for isBadVersion()
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 *
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 * @param {integer} version number
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 * @return {boolean} whether the version is bad
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 * isBadVersion = function(version) {
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 * ...
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 * };
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 */
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/**
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 * @param {function} isBadVersion()
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 * @return {function}
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 */
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var solution = function (isBadVersion) {
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  /**
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   * @param {integer} n Total versions
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   * @return {integer} The first bad version
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   */
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  return function (n) {
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    let ceiling = n;
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    let floor = 1;
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    let firstBadVersion = -1;
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    while (floor <= ceiling) {
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      const middle = Math.floor((ceiling + floor) / 2);
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      if (isBadVersion(middle)) {
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        firstBadVersion = middle;
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        ceiling = middle - 1;
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      } else {
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        floor = middle + 1;
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      }
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    }
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    return firstBadVersion;
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  };
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};