Maximum Building Height LeetCode solution in JavaScript

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/**
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 * @param {number} n
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 * @param {number[][]} restrictions
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 * @return {number}
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 */
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var maxBuilding = function (n, restrictions) {
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  let maxHeight = 0;
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  restrictions.push([1, 0]); //Push extra restriction as 0 for 1
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  restrictions.push([n, n - 1]); //Push extra restrition as n-1 for n
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  restrictions.sort(function (a, b) {
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    return a[0] - b[0];
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  });
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  //Propogate from left to right to tighten the restriction: Check building restriction can be furhter tightened due to the left side building restriction.
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  for (let i = 1; i < restrictions.length; i++) {
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    restrictions[i][1] = Math.min(
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      restrictions[i][1],
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      restrictions[i][0] - restrictions[i - 1][0] + restrictions[i - 1][1]
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    );
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  }
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  //Propogate from right to left to tighten the restriction: Check building restriction can be furhter tightened due to the right side building restriction.
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  for (let i = restrictions.length - 2; i >= 0; i--) {
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    restrictions[i][1] = Math.min(
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      restrictions[i][1],
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      restrictions[i + 1][0] - restrictions[i][0] + restrictions[i + 1][1]
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    );
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  }
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  let max = 0;
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  for (let i = 0; i < restrictions.length - 1; i++) {
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    let leftHeight = restrictions[i][1];
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    let rightHeight = restrictions[i + 1][1];
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    let distance = restrictions[i + 1][0] - restrictions[i][0] - 1; //Number of cities between ith and i+1th city, excluding these cities
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    let hightDiff = Math.abs(restrictions[i + 1][1] - restrictions[i][1]);
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    let middleHeight =
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      Math.max(leftHeight, rightHeight) + Math.ceil((distance - hightDiff) / 2);
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    max = Math.max(max, middleHeight);
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  }
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  return max;
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};