Minimum Operations to Convert Number LeetCode solution in Java

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class Solution {
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  public int minimumOperations(int[] nums, int start, int goal) {
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    int res = 0;
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    Queue<Integer> q = new LinkedList<>();
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    Set<Integer> set = new HashSet<>();
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    q.offer(start);
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    while (!q.isEmpty()) {
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      int size = q.size();
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      for (int i = 0; i < size; i++) {
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        int val = q.poll();
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        if (val == goal) return res;
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        if ((val < 0 || val > 1000) || set.contains(val)) continue;
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        if (!set.contains(val)) set.add(val);
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        for (int num : nums) {
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          q.offer(val + num);
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          q.offer(val - num);
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          q.offer(val ^ num);
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        }
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      }
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      res++;
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    }
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    return -1;
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  }
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}