Adding a Hackerrank Problem along with the Solution to Stack Folder #75

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	import java.io.*;
	import java.util.*;

	public class MaximumElement {

	public static void main(String[] args) {
	Scanner sc = new Scanner(System.in);
	int n = sc.nextInt();
	Stack<Integer> maxStack = new Stack<>();
	ArrayDeque<Integer> stack = new ArrayDeque<>();
	for(int i=0;i<n;i++){

	int c = sc.nextInt();

	switch (c){
	case 1 : int val = sc.nextInt();
	stack.push(val);
	if(maxStack.isEmpty() \|\| val>=maxStack.peek()){
	maxStack.push(val);
	}
	break;

	case 2 : int popped = stack.pop();
	if(popped == maxStack.peek()){
	maxStack.pop();
	}
	break;

	case 3 :
	System.out.println(maxStack.peek());
	break;

	default: break;
	}
	}
	sc.close();
	}
	}

28 changes: 28 additions & 0 deletions Practice Problems/Stack/Maximum Element/README.md

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	# Maximum Element
	### Problem from Hackerrank Practice > DataStructures > Stacks

	You have an empty sequence, and you will be given N queries. Each query is one of these three types:

	- 1 x -Push the element x into the stack.
	- 2 -Delete the element present at the top of the stack.
	- 3 -Print the maximum element in the stack.

	The first line of input contains an integer, N . The next N lines each contain an above mentioned query. (It is guaranteed that each query is valid.)

	## Example:
	### Input:<br>
	10<br>
	1 97<br>
	2<br>
	1 20<br>
	2<br>
	1 26<br>
	1 20<br>
	2<br>
	3<br>
	1 91<br>
	3<br>

	### Output:<br>
	26<br>
	91<br>

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