Minimum Jumps to Reach Home LeetCode solution in Java

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class Solution {
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  public int minimumJumps(int[] forbidden, int a, int b, int x) {
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    // Visited Set
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    Set<Integer> visited = new HashSet<Integer>();
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    // Add forbidden coordinates to visited
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    for (int i = 0; i < forbidden.length; i++) {
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      visited.add(forbidden[i]);
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    }
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    // Distance/ Jumps map
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    Map<Integer, Integer> jumps = new HashMap<>();
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    jumps.put(0, 0);
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    // BFS Queue
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    Queue<Integer[]> q = new LinkedList<>();
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    q.add(new Integer[] {0, 1});
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    // BFS
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    while (q.size() != 0) {
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      Integer[] ud = q.poll();
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      int u = ud[0], d = ud[1];
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      // x found
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      if (u == x) {
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        return jumps.get(u);
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      }
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      // jump right
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      if (u + a < 6001 && !visited.contains(u + a)) {
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        q.add(new Integer[] {u + a, 1});
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        visited.add(u + a);
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        jumps.put(u + a, jumps.get(u) + 1);
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      }
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      // jump left
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      if (d != -1 && u - b > -1 && !visited.contains(u - b)) {
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        q.add(new Integer[] {u - b, -1});
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        jumps.put(u - b, jumps.get(u) + 1);
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      }
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    }
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    return -1;
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  }
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}