Day_4.java

public class Person {
    private int age;	
  
	public Person(int initialAge) {
  		// Add some more code to run some checks on initialAge
        if( initialAge < 0 ){
            System.out.println("Age is not valid, setting age to 0.");
            initialAge = 0;
        }
        this.age = initialAge;
	}

	public void amIOld() {
  		// Write code determining if this person's age is old and print the correct statement:
        if( age < 13 )
            System.out.println("You are young.");
	    else if( age >= 13 && age < 18 )
            System.out.println("You are a teenager.");
	       else     
             System.out.println("You are old.");
	        
   }

	public void yearPasses() {
  		// Increment this person's age.
	       age +=1;
    }