Maximum Candies You Can Get from Boxes LeetCode solution in Java

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class Solution {
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  public int maxCandies(
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      int[] status, int[] candies, int[][] keys, int[][] containedBoxes, int[] initialBoxes) {
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    int n = initialBoxes.length;
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    if (n == 0) return 0;
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    Queue<Integer> q = new LinkedList<>();
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    int totalCandies = 0;
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    for (int i : initialBoxes) {
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      if (status[i] == 0) {
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        q.add(i);
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      } else {
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        totalCandies += candies[i]; // Add all Candies of intial box;
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        for (int j = 0; j < containedBoxes[i].length; j++) {
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          q.add(containedBoxes[i][j]); // Add all Contained Boxes in queue;
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        }
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        for (int j = 0; j < keys[i].length; j++) {
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          status[keys[i][j]] = 1; // Set status of of box=1 if we found key;
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        }
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      }
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    }
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    while (q.size() > 0 && isValid(q, status)) {
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      int b = q.poll();
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      if (status[b] == 1) {
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        totalCandies += candies[b]; // Add all Candies of selected box;
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        for (int j = 0; j < containedBoxes[b].length; j++) {
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          q.add(containedBoxes[b][j]); // Add all Contained Boxes in queue;
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        }
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        for (int j = 0; j < keys[b].length; j++) {
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          status[keys[b][j]] = 1; // Set status of of box=1 if we found key;
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        }
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      } else q.add(b); // If Status==0 add again in queue;
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    }
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    return totalCandies;
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  }
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  /* This function helps to know whether any boxes in queue status is still open or not
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  if all boxes status is off then it will return false and above while loop while terminate beacue now  we cannot get any candy*/
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  public boolean isValid(Queue<Integer> q, int[] status) {
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    Queue<Integer> cq = new LinkedList<>(q);
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    while (cq.size() > 0) {
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      if (status[cq.poll()] == 1) return true;
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    }
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    return false;
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  }
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}