Write a program to sort a stack in ascending order

Question

Can someone help look at my code, please? Thank you so much for your help. The input stack is [5, 2, 1, 9, 0, 10], my codes gave output stack [0, 9, 1, 2, 5, 10], 9 is not i

Answer 1

Here's my version of the code which is pretty straightforward to follow.

import java.util.Stack;

public class StackSorting {

    public static void main(String[] args) {
        Stack stack = new Stack();

        stack.push(12);
        stack.push(100);
        stack.push(13);
        stack.push(50);
        stack.push(4);

        System.out.println("Elements on stack before sorting: "+ stack.toString());

        stack = sort(stack);

        System.out.println("Elements on stack after sorting: "+ stack.toString());

    }

    private static Stack sort(Stack stack) {

        if (stack.isEmpty()) {
            return null;
        }

        Stack sortedStack = new Stack();

        int element = 0;
        while(!stack.isEmpty()) {
            if (stack.peek() <= (element = stack.pop())) {
                if (sortedStack.isEmpty()) {
                    sortedStack.push(element);
                } else {
                    while((!sortedStack.isEmpty()) && sortedStack.peek() > element) {
                        stack.push(sortedStack.pop());
                    }
                    sortedStack.push(element);
                }
            }
        }

        return sortedStack;
    }
}