Minimum Garden Perimeter to Collect Enough Apples LeetCode solution in JavaScript

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/**
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 * @param {number} neededApples
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 * @return {number}
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 */
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var minimumPerimeter = function (neededApples) {
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  let start = 2,
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    n = 1,
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    dp = [0];
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  while (true) {
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    let cur = start,
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      res = dp[n - 1];
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    //Add the X and Y axis apples multiplied with 4
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    res += (cur + cur - n) * 4;
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    // Add the interior apples using and AP formula of  ( n - 1 ) / 2 * (2a + ( n-1 ) * d ) & multiplying it by 8 as count is 8
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    res += ((n - 1) / 2) * (2 * (cur - 1) + (n - 2) * -1) * 8;
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    //Setting the result to DP
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    dp[n] = res;
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    //If current state is greater than or equal to needed then return the perimeter
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    if (neededApples <= res) return 8 * n;
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    n++;
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    start += 2;
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  }
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};