Reverse First K elements of Queue
Easy Accuracy: 57.92% Submissions: 19271 Points: 2

Given an integer K and a queue of integers, we need to reverse the order of the first K elements of the queue, leaving the other elements in the same relative order.

Only following standard operations are allowed on queue.

  • enqueue(x) : Add an item x to rear of queue
  • dequeue() : Remove an item from front of queue
  • size() : Returns number of elements in queue.
  • front() : Finds front item.

Example 1:

Input:
5 3
1 2 3 4 5

Output: 
3 2 1 4 5

Explanation: 
After reversing the given
input from the 3rd position the resultant
output will be 3 2 1 4 5.

Example 2:

Input:
4 4
4 3 2 1

Output: 
1 2 3 4

Explanation: 
After reversing the given
input from the 4th position the resultant
output will be 1 2 3 4.

Your Task:
Complete the provided function modifyQueue that takes queue and k as parameters and returns a modified queue. The printing is done automatically by the driver code.

Expected TIme Complexity : O(n)
Expected Auxilliary Space : O(n)

Constraints:
1 <= N <= 1000
1 <= K <= N

Note:The Input/Ouput format and Example given are used for system's internal purpose, and should be used by a user for Expected Output only. As it is a function problem, hence a user should not read any input from stdin/console. The task is to complete the function specified, and not to write the full code.

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