Longest Continuous Subarray With Absolute Diff Less Than or Equal to Limit LeetCode solution in Java

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class Solution {
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  public int longestSubarray(int[] nums, int limit) {
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    Deque<Integer> increasing = new LinkedList<Integer>(); // To keep track of Max_value index
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    Deque<Integer> decreasing = new LinkedList<Integer>(); // To keep track of Min_value index
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    int i = 0;
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    int j = 0;
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    int max_length = 0;
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    while (j < nums.length) {
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      while (!increasing.isEmpty() && nums[increasing.peekLast()] >= nums[j]) {
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        increasing.pollLast();
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      }
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      increasing.add(j);
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      while (!decreasing.isEmpty() && nums[decreasing.peekLast()] <= nums[j]) {
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        decreasing.pollLast();
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      }
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      decreasing.add(j);
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      int max_val = nums[decreasing.peekFirst()];
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      int min_val = nums[increasing.peekFirst()];
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      if (max_val - min_val <= limit) {
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        max_length = Math.max(max_length, j - i + 1);
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      } else {
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        // If maximum absolute diff > limit , then remove from dequeue and increase i
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        while (i <= j && nums[decreasing.peekFirst()] - nums[increasing.peekFirst()] > limit) {
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          if (!increasing.isEmpty() && increasing.peekFirst() == i) {
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            increasing.pollFirst();
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          }
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          if (!decreasing.isEmpty() && decreasing.peekFirst() == i) {
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            decreasing.pollFirst();
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          }
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          i++;
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        }
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      }
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      j++;
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    }
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    return max_length;
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  }
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}