82 lines
1.8 KiB
Java
82 lines
1.8 KiB
Java
// Generic Stack class
|
|
class Stack<T> {
|
|
|
|
private Object[] elements;
|
|
private int top;
|
|
private static final int DEFAULT_SIZE = 10;
|
|
|
|
public Stack() {
|
|
elements = new Object[DEFAULT_SIZE];
|
|
top = -1;
|
|
}
|
|
|
|
public void push(T item) {
|
|
elements[++top] = item;
|
|
}
|
|
|
|
public T pop() {
|
|
if (isEmpty()) return null;
|
|
return (T) elements[top--];
|
|
}
|
|
|
|
public boolean isEmpty() {
|
|
return top == -1;
|
|
}
|
|
}
|
|
|
|
// Student class
|
|
class Student {
|
|
|
|
private String name;
|
|
private int id;
|
|
|
|
public Student(String name, int id) {
|
|
this.name = name;
|
|
this.id = id;
|
|
}
|
|
|
|
public String toString() {
|
|
return "Student [name=" + name + ", id=" + id + "]";
|
|
}
|
|
}
|
|
|
|
// Employee class
|
|
class Employee {
|
|
|
|
private String name;
|
|
private String department;
|
|
|
|
public Employee(String name, String department) {
|
|
this.name = name;
|
|
this.department = department;
|
|
}
|
|
|
|
public String toString() {
|
|
return "Employee [name=" + name + ", department=" + department + "]";
|
|
}
|
|
}
|
|
|
|
public class Main {
|
|
|
|
public static void main(String[] args) {
|
|
// Stack of Students
|
|
Stack<Student> studentStack = new Stack<>();
|
|
studentStack.push(new Student("John", 101));
|
|
studentStack.push(new Student("Mary", 102));
|
|
|
|
System.out.println("Students popped from stack:");
|
|
while (!studentStack.isEmpty()) {
|
|
System.out.println(studentStack.pop());
|
|
}
|
|
|
|
// Stack of Employees
|
|
Stack<Employee> employeeStack = new Stack<>();
|
|
employeeStack.push(new Employee("Bob", "IT"));
|
|
employeeStack.push(new Employee("Alice", "HR"));
|
|
|
|
System.out.println("\nEmployees popped from stack:");
|
|
while (!employeeStack.isEmpty()) {
|
|
System.out.println(employeeStack.pop());
|
|
}
|
|
}
|
|
}
|