Implement a Queue using 2 stacks s1 and s2 .

Input Format:
The first line of the input contains an integer 'T' denoting the number of test cases. Then T test cases follow.
First line of each test case contains an integer Q denoting the number of queries . 
A Query Q is of 2 Types
(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)
The second line of each test case contains Q queries seperated by space.

Output Format:
The output for each test case will  be space separated integers having -1 if the queue is empty else the element poped out from the queue . 
You are required to complete the two methods push which take one argument an integer 'x' to be pushed into the quee and pop which returns a integer poped out from other queue.

Your Task:
Since this is a function problem, you don't need to take inputs. Just complete the provided functions. The printing is done automatically by the driver code.

Constraints:
1 <= T <= 100
1 <= Q <= 100
1 <= x <= 100

Example:
Input

2
5
1 2 1 3 2 1 4 2
4
1 2 2 2 1 4
Output
2 3
2 -1

Explanation:
Testcase1:
1 2    the quee 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 


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.

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

Contributor: Amit Khandelwal
Author: Shubham Joshi 1


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