Get minimum element from stack
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  Difficulty: Medium   Marks: 4

You are given N elements and your task is to Implement a Stack in which you can get minimum element in O(1) time.

Input:
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 may be of 3 Types:
    1. 1 x (a query of this type means  pushing 'x' into the stack)
    2. 2 (a query of this type means to pop element from stack and print the poped element)
    3. 3 (a query of this type means to print the minimum element from the stack)
The second line of each test case contains Q queries seperated by space.

Output:
The output for each test case will  be space separated integers having -1 if the stack is empty else the element poped out  or min element from the stack.

User Task:
You are required to complete the three methods push() which take one argument an integer 'x' to be pushed into the stack, pop() which returns a integer poped out from the stack and getMin() which returns the min element from the stack.

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

Example:
Input:

1
6
1 2 1 3 2 3 1 1 3   

Output:
3 2 1

Explanation:
Testcase 1:
In the first test case for query 
1 2  the stack will be {2}
1 3  the stack will be {2 3}
2 poped element will be 3 the stack will be {2}
3 min element will be 2 
1 1 the stack will be {2 1}
3 min element will be 1 and

 

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

Contributor: Amit Khandelwal
Author: Shubham Joshi 1


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