Best Time to Buy and Sell Stock III LeetCode solution in JavaScript

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var maxProfit = function (prices) {
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  if (prices.length == 0) return 0;
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  let dp = new Array(prices.length).fill(0);
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  let min = prices[0];
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  let max = 0;
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  for (let i = 1; i < prices.length; i++) {
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    min = Math.min(min, prices[i]); // or Math.min(min, prices[i] - dp[i]) , FYI: dp[i] is 0
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    max = Math.max(max, prices[i] - min);
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    dp[i] = max;
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  }
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  // 1st run dp = [0,0,2,2,2,3,3,4];
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  min = prices[0];
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  max = 0;
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  for (let i = 1; i < prices.length; i++) {
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    min = Math.min(min, prices[i] - dp[i]); // substract dp[i]  = current price - what profit we made during 1st run.
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    max = Math.max(max, prices[i] - min);
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    dp[i] = max;
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  }
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  // 2nd run dp = [0,0,2,2,2,5,5,6];
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  return dp.pop();
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};