Best Time to Buy and Sell Stock with Transaction Fee LeetCode solution in Java

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class Solution {
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  public int maxProfit(int[] prices, int fee) {
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    int[][] dp = new int[prices.length][2];
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    for (int[] a : dp) {
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      a[0] = -1;
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      a[1] = -1;
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    }
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    return profit(prices, fee, 0, 1, dp);
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  }
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  public int profit(int[] prices, int fee, int i, int buy, int[][] dp) {
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    if (i == prices.length) {
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      return 0;
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    }
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    if (dp[i][buy] != -1) {
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      return dp[i][buy];
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    }
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    int maxProfit = 0;
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    if (buy == 1) {
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      int yesBuy = profit(prices, fee, i + 1, 0, dp) - prices[i];
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      int noBuy = profit(prices, fee, i + 1, 1, dp);
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      maxProfit = Math.max(yesBuy, noBuy);
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    } else {
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      int yesSell = prices[i] - fee + profit(prices, fee, i + 1, 1, dp);
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      int noSell = profit(prices, fee, i + 1, 0, dp);
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      maxProfit = Math.max(yesSell, noSell);
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    }
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    return dp[i][buy] = maxProfit;
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  }
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}