Problem of the Day

Monday, October 21, 2024

Problem:

The CookieJar class is an abstraction of a cookie jar that holds a number of cookies, numCookies, all of the same type, cookieName. A partial listing of the class description is given here.

public class CookieJar
{
    private String cookieName;
    private int numCookies;

    /* constructor and some methods not shown */

    /**
     * The eatCookie method reduces the number of cookies in
     * the jar by 1, if there are still cookies in the jar.
     * Additionally, an error code is returned with a value
     * of 0 if the cookie was successfully eaten, or -1
     * if a cookie couldn't be eaten.
     * @return 0 if cookie eaten, -1 if eating a cookie failed
     */
    public int eatCookie()
    {   /* code not shown */ }
}

Which code below could successfully be used for the eatCookie method?

1. 
   

   if (numCookies > 1)
       numCookies--;
       return 0;
   else
       return -1;

2. 
   

   if (numCookies >= 0)
   {
       numCookies--;
       return 0;
   }
   else
   {
       return -1;
   }

3. 
   

   if (numCookies > 0)
   {
       return 0;
       numCookies--;
   }
   else
   {
       return -1;
   }

4. 
   

   if (numCookies > 0)
   {
       numCookies--;
       return 0;
   }
   else
   {
       return -1;
   }

Show solution: