Maximum Split of Positive Even Integers LeetCode solution in Java

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class Solution {
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  public List<Long> maximumEvenSplit(long finalSum) {
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    List<Long> res = new ArrayList<Long>();
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    // odd sum cannot be divided into even numbers
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    if (finalSum % 2 != 0) {
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      return res;
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    }
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    // Greedy approach, try to build the total sum using minimum unique even nos
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    long currNum = 2;
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    long remainingSum = finalSum;
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    // as long as we can add subtract this number from remaining sum
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    while (currNum <= remainingSum) {
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      res.add(currNum);
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      remainingSum -= currNum; // reducing remaining sum
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      currNum += 2; // next even number
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    }
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    // now, remaining sum cannot be fulfilled by any larger even number
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    // so extract the largest even number we added to the last index of res, and make it even larger
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    // by adding this current remaining sum
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    // add remaining sum to the last element
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    long last = res.remove(res.size() - 1);
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    res.add(last + remainingSum);
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    return res;
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  }
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}