Timer is Running

Implement a Queue using an Array. Queries in the Queue are of the following type:
(i) 1 x   (a query of this type means  pushing 'x' into the queue)
(ii) 2     (a query of this type means to pop element from queue and print the poped element)

Example 1:

Input:
Q = 5
Queries = 1 2 1 3 2 1 4 2
Output: 2 3
Explanation:
In the first test case for query 
1 2 the queue will be {2}
1 3 the queue will be {2 3}
2   poped element will be 2 the 
    queue will be {3}
1 4 the queue will be {3 4}
2   poped element will be 3 

Example 2:

Input:
Q = 4
Queries = 1 3 2 2 1 4   
Output: 3 -1
Explanation:
In the second testcase for query 
1 3 the queue will be {3}
2   poped element will be 3 the
    queue will be empty
2   there is no element in the
    queue and hence -1
1 4 the queue will be {4}. 

Your Task :
You are required to complete the two methods push() which take one argument an integer 'x' to be pushed into the queue and pop() which returns a integer poped out from othe queue. If the queue is empty, it should return -1 on a pop operation. 

Expected Time Complexity: O(1) for both push() and pop().
Expected Auxiliary Space: O(1) for both push() and pop().

Constraints:
1 <= Q <= 105
1 <= x <= 105

** For More Input/Output Examples Use 'Expected Output' option **

Contributor: Amit Khandelwal
Author: Shubham Joshi 1


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