Stack Reverse (O(n*2) time O(n) space)

	package linkedList;
	import java.util.Stack;
	public class StackReversal {
	public static void main(String args[]) {
	Stack<Integer> stack = new Stack<Integer>();
	stack.push(1);
	stack.push(2);
	stack.push(3);
	System.out.println(stack.toString());
	reverseStack(stack);
	System.out.println(stack.toString());
	}
	private static void reverseStack(Stack<Integer> stack) {
	if(stack.isEmpty()) {
	return;
	}
	int temp =stack.pop();
	reverseStack(stack);
	insertAtBottom(stack,temp);
	}
	private static void insertAtBottom(Stack<Integer> stack, int data) {
	if(stack.isEmpty()) {
	stack.push(data);
	return;
	}
	int temp = stack.pop();
	insertAtBottom(stack, data);
	stack.push(temp);
	}
	}

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