Couples Holding Hands LeetCode solution in Java

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class Solution {
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  public int minSwapsCouples(int[] row) { // Union -Find pairs for 2
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    Map<Integer, Integer> parents = new HashMap<>();
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    int count = 0;
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    for (int i = 0; i < row.length; i += 2) {
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      int parent = Math.min(row[i], row[i + 1]);
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      int child = Math.max(row[i], row[i + 1]);
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      parents.put(parent, child);
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    }
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    for (int i = 0; i < row.length; i += 2) {
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      if ((parents.containsKey(i) && parents.get(i) == (i + 1))
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          || (parents.containsKey(i - 1) && parents.get(i - 1) == i)) continue;
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      count += 1;
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      int curChild = parents.get(i);
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      int correctChildsChild = parents.get(i + 1);
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      parents.remove(i + 1); // remove mapping of 1 in eg) //0,2 ; 1,3
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      parents.put(Math.min(curChild, correctChildsChild), Math.max(curChild, correctChildsChild));
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      // add mapping 2->7 , also place smaller number as parent for eg)//0,4 ; 1,3
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      parents.put(i, i + 1);
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    }
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    return count;
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  }
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}