Maximum Score of a Good Subarray LeetCode solution in JavaScript

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/*
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	JAVASCRIPT
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 */
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var maximumScore = function (nums, k) {
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  // iterate to the left to update the minimum value at each index
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  let min = nums[k];
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  for (let i = k - 1; i >= 0; i--) {
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    min = Math.min(min, nums[i]);
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    nums[i] = min;
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  }
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  // iterate to the right to update the minimum value at each index
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  min = nums[k];
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  for (let i = k + 1; i < nums.length; i++) {
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    min = Math.min(min, nums[i]);
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    nums[i] = min;
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  }
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  // start with 2 pointers at opposite ends of nums
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  let left = 0;
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  let right = nums.length - 1;
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  let bestScore = 0;
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  while (left <= right) {
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    bestScore = Math.max(
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      bestScore,
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      Math.min(nums[left], nums[right]) * (right - left + 1)
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    );
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    // first to check if either pointer is at k
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    // if it is at k then we must move the other pointer inwards
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    if (left === k) {
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      right--;
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    } else if (right === k) {
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      left++;
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      // if neither index is at k move the pointer
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      // that is smaller inwards
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    } else if (nums[left] < nums[right]) {
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      left++;
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    } else {
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      right--;
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    }
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  }
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  return bestScore;
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};