Simulated access

public class Test{
     static int[] arr=new int[30];
     static int flag=0; 
public static void main(String[] args){
put(20);
put(30);
put(40);
put(50);
put(60);
get();
get();
show();
}

public static void put(int x){
arr[flag]=x;
flag++;
}

public static void get(){
int re=arr[flag-1];
flag--;
System.out.println(re);

}
public static void show(){
for(int i=0;i<flag;i++){
System.out.println(arr[i]);
}
}
}