Implement two stacks in an array
Submissions: 20076   Accuracy:

49.76%

  Difficulty: Easy   Marks: 2

Your task is to implement  2 stacks in one array efficiently .

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 4 Types
(i)    1 1 x    (a query of this type means  pushing 'x' into the stack 1)
(ii)   1 2      (a query of this type means to pop element from stack1  and print the poped element)
(iii)  2 1 x  (a query of this type means pushing 'x' into the stack 2)
(iv)  2 2     (a query of this type means to pop element from stack2 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 stack is empty else the element poped out from the stack. 
You are required to complete the 4  methods push1, push2 which takes one argument an integer 'x' to be pushed into the stack one and two  and pop1, pop2 which returns a integer poped out from stack one and two .

Your Task:
Since this is a function problem, you don't need to take any input. Just complete the provided functions.

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

Example:
Input

2
6
1 1 2 1 1 3 2 1 4 1 2 2 2 2 2
4
1 1 2 2 2 1 2 2 2
Output
3 4 -1
-1 2 -1

Explanation:
Testcase1:
1 1 2    the stack1 will be {2}
1 1 3    the stack1 will be {2,3}
2 1 4   the stack2 will be {4}
1 2      the poped element will be 3 from stack1 and stack1 will be {2}
2 2      the poped element will be 4 from stack2 and now stack2 is empty
2 2      the stack2 is now empty hence -1 .

 

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

Contributor: Amit Khandelwal
Author: Shubham Joshi 1


If you have purchased any course from GeeksforGeeks then please ask your doubt on course discussion forum. You will get quick replies from GFG Moderators there.



Need help with your code? Please use ide.geeksforgeeks.org, generate link and share the link here.


to report an issue on this page.