Implementation of a stack in java which, in addition to push and pop, also has a function min which returns the minimum element. Push, pop and min should all operate in O(1) time

import java.util.Stack;

public class StackWithMin extends Stack{

                private static final long serialVersionUID = 1L;

                Stack s;

               

                StackWithMin(){

                                s=new Stack();

                }

               

 public   void push(int n) {

                                if(n<=min()) {

                                                s.push(n);

                                }

                                super.push(n);

                }

               

                public Integer pop() {

                                int value=super.pop();

                                if(value==s.peek()) {

                                                s.pop();

                                }

                                return value;

                }

               

                int min() {

                                if(s.isEmpty()) {

                                                return Integer.MAX_VALUE;

                                }else {

                                return   s.peek();

                                }

                }

                public static void main(String[] args) throws IOException {

                                // Test harness

                                int[] arr= {1,0,2,7,-2,8,12,5,3};

                                StackWithMin stck=new StackWithMin();

                                for(int i=0;i<arr.length;i++){

                                                stck.push(arr[i]);                             

                                }

                                System.out.println("min element: "+stck.min());

                                System.out.println("Now popping the element one by one from stack and find minimum element on the stack as below: ");

                               

                                while(!stck.isEmpty()) {

                                                System.out.print("popped elemnet: "+stck.pop());

                                                if(!stck.isEmpty()) {

                                                    System.out.println(" now min element on the stack is: "+stck.min());

                                                }else {

                                                                System.out.println(" Now Stack is empty");

                                                }

                                }

                }

               

               

               

}