Generate Parentheses LeetCode solution in Java

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class Solution {
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  List<String> s = new ArrayList<>();
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  public void get(int n, int x, String p) {
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    if (n == 0 && x == 0) {
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      s.add(p);
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      return;
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    }
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    if (n == 0) {
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      get(n, x - 1, p + ")");
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    } else if (x == 0) {
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      get(n - 1, x + 1, p + "(");
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    } else {
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      get(n, x - 1, p + ")");
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      get(n - 1, x + 1, p + "(");
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    }
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  }
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  public List<String> generateParenthesis(int n) {
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    s.clear();
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    get(n, 0, "");
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    return s;
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  }
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}