The following solution also passed all the test cases. When compared to the solution provided by the author, the only difference is that I used if block to remove out of range elements from the dequeue instead of a while loop. I am having hard time to come up with a test case where my code fails but the solution that has while loop to remove out of range elements from the dequeue succeeds.

public class Solution {

public List<int> printMax(int[] arr, int k) {

    List<int> result = new List<int>();

    // ToDo: Write Your Code Here.

    LinkedList<int> dequeue = new LinkedList<int>();



    for (int i = 0; i < arr.Length; i++) 

    {

        if (dequeue.Count > 0 && dequeue.First.Value < i - k + 1)

            dequeue.RemoveFirst();

        

        while (dequeue.Count > 0 && arr[dequeue.Last.Value] <= arr[i])

            dequeue.RemoveLast();



        dequeue.AddLast(i);



        if (i >= k - 1)

            result.Add(arr[dequeue.First.Value]);

    }

    

    return result;

}

}