Check if Every Row and Column Contains All Numbers LeetCode solution in Java

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class Solution {
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  public boolean checkValid(int[][] matrix) {
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    int n = matrix.length;
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    int num = (n * (n + 1)) / 2; // SUM of n number 1 to n;
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    for (int i = 0; i < n; i++) {
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      HashSet<Integer> hs = new HashSet<Integer>();
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      HashSet<Integer> hs1 = new HashSet<Integer>();
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      int m = num;
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      int k = num;
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      for (int j = 0; j < n; j++) {
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        hs.add(matrix[i][j]);
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        hs1.add(matrix[j][i]);
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        m -= matrix[i][j];
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        k -= matrix[j][i];
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      }
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      if (m != 0 || k != 0 || hs.size() != n || hs.size() != n) {
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        return false;
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      }
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    }
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    return true;
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  }
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}