Write a class named ParkingMeter containing: Two instance variables named timeLeft and maxTime of type int . The value of timeLeft should be initialized to 0.

LANGUAGE: JAVA

CHALLENGE:

Write a class named ParkingMeter containing:
Two instance variables named timeLeft and maxTime of type int . The value of timeLeft should be initialized to 0.
A constructor accepting a single integer parameter whose value is used to initialize the maxTime instance variable .
A method named add that accepts an integer parameter . If the value of the parameter is equal to 25, the value of timeLeft is increased by 30; otherwise no increase is performed. Furthermore, the increase occurs only if the value of timeLeft will not exceed the value of maxTime. add returns a boolean value : true if timeLeft was increase , false otherwise.
A method named tick that accepts no parameters and returns no value . tick decreases the value of timeLeft by 1, but only if the value of timeLeft is greater than 0.
A method named isExpired that accepts no parameters . isExpired returns a boolean value : true if the value of timeLeft is equal to 0; false otherwise.

SOLUTION:

public class ParkingMeter{
    private int timeLeft = 0 ;
    private int maxTime;
    public ParkingMeter(int x) {
        this.maxTime=x;
    }
    public boolean add (int y){
        if ((y == 25) && (timeLeft < maxTime)) { 
            timeLeft += 30; return true; 
        } 
        else return false; 
    } 
    public void tick() { 
        if (timeLeft > 0)
        timeLeft–;
    }
    public boolean isExpired(){
        if(timeLeft==0) return true; else return false;
    }
}