Couples Holding Hands LeetCode solution in C++

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class Solution {
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 public:
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  int minSwapsCouples(vector<int> &row) {
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    int cnt = 0, n = row.size();
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    // first of all making row element equal  ex for [0,1],[2,3] --> [0,0]
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    // ,[2,2]
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    for (auto &x : row) {
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      if (x & 1) {
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        x--;
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      }
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    }
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    for (int i = 0; i < n; i += 2) {
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      int ele = row[i];
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      int j = i + 1;
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      // for every num find location of equal one,
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      while (j < n and row[j] != ele) j++;
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      if (j != i + 1) {
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        // not in same couch then cnt++ , and swap
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        swap(row[j], row[i + 1]);
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        cnt++;
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      }
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    }
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    return cnt;
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  }
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};