Maximum Score from Performing Multiplication Operations LeetCode solution in Java

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class Solution {
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  public int maximumScore(int[] nums, int[] multipliers) {
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    int n = nums.length, m = multipliers.length;
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    return helper(nums, multipliers, 0, 0, n - 1, new Integer[m][m]);
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  }
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  public int helper(int[] nums, int[] multipliers, int idx, int left, int right, Integer[][] memo) {
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    if (idx == multipliers.length) return 0;
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    if (memo[idx][left] != null) return memo[idx][left];
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    int takeLeft =
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        nums[left] * multipliers[idx] + helper(nums, multipliers, idx + 1, left + 1, right, memo);
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    int takeRight =
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        nums[right] * multipliers[idx] + helper(nums, multipliers, idx + 1, left, right - 1, memo);
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    return memo[idx][left] = Math.max(takeLeft, takeRight);
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  }
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}