Minimum Number of Operations to Reinitialize a Permutation LeetCode solution in C++

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class Solution {
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 public:
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  vector<int> change(vector<int> arr, vector<int> v) {
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    int n = v.size();
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    for (int i = 0; i < n; i++) {
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      if (i % 2 == 0) {
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        arr[i] = v[i / 2];
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      } else {
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        arr[i] = v[(n / 2) + ((i - 1) / 2)];
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      }
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    }
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    return arr;
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  }
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  int reinitializePermutation(int n) {
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    vector<int> v(n);
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    for (int i = 0; i < n; i++) {
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      v[i] = i;
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    }
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    vector<int> arr(n);
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    arr = change(arr, v);
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    if (arr == v) {
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      return 1;
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    }
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    int cnt = 1;
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    while (arr != v) {
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      arr = change(arr, arr);
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      cnt++;
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      if (arr == v) {
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        return cnt;
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      }
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    }
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    return cnt;
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  }
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};