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Java Java Objects Creating the MVP Conference Registration Assistant

Posted by kajoka rogers
kajoka rogers
Courses Plus Student 593 Points

sorry any one just help me this quiz because i don'y have even idea on how to start this quiz ,how can i set lines?

sorry help me please

ConferenceRegistrationAssistant.java 
public class ConferenceRegistrationAssistant {

  /**
   * Assists in guiding people to the proper line based on their last name.
   *
   * @param lastName The person's last name
   * @return The line number based on the first letter of lastName
   */
  public int getLineNumberFor(String lastName) {
    int lineNumber = 0;
    /*
      lineNumber should be set based on the first character of the person's last name
      Line 1 - A thru M
      Line 2 - N thru Z

     */
    return lineNumber;
  }

}
Example.java 
public class Example {

  public static void main(String[] args) {
    /*
      IMPORTANT:  You can compare characters using <, >. <=, >= and == just like numbers
     */
    if ('C' < 'D') {
      System.out.println("C comes before D");
    }

    if ('B' > 'A') {
      System.out.println("B comes after A");
    }

    if ('E' >= 'E') {
      System.out.println("E is equal to or comes after E");
    }

    // This code is here for demonstration purposes only...
    ConferenceRegistrationAssistant assistant = new ConferenceRegistrationAssistant();
    /*
      Remember that there are 2 lines.
      Line #1 is for A-M
      Line #2 is for N-Z
     */
    int lineNumber = 0;
    /*
      This should set lineNumber to 2 because
      The last name is Zimmerman which starts with a Z.
      Therefore it is between N-Z
     */
    lineNumber = assistant.getLineNumberFor("Zimmerman");

    /*
      This method call should set lineNumber to 1, because 'A' from "Anderson" is between A-M.
     */
    lineNumber = assistant.getLineNumberFor("Anderson");

    /*
      Likewise Charlie Brown's 'B' is between 'A' and 'M', so lineNumber should be set to 1
     */
    lineNumber = assistant.getLineNumberFor("Brown");
  }

}

1 Answer

Eric M
Eric M
11,546 Points
Eric M
Eric M
11,546 Points

Hi kajoka,

The requirement for this challenge is Fix the getLineNumberFor method to return a 1 if the first character of lastName is between A and M or else return 2 if it is between N and Z.

So let's ignore everything around this and take a look at the getLineNumberFor method

  public int getLineNumberFor(String lastName) {
    int lineNumber = 0;
    /*
      lineNumber should be set based on the first character of the person's last name
      Line 1 - A thru M
      Line 2 - N thru Z

     */
    return lineNumber;

We have a parameter lastName that's a string, we need to set the variable lineNumber based on the first letter of this string and then return lineNumber

We can get the first letter of a string with the charAt() string method using the index of the first character (0).

We might also want to convert this character to a consistent case but we won't worry about that now.

It's possible to compare characters using greater than and less than, so we can just see if the first letter is less than or equal to M (that'll cover A through M) and return 1, otherwise we return 2

  public int getLineNumberFor(String lastName) 
  {
          int lineNumber = 0;

          if (lastName.charAt(0) <= 'M')
          {
                    lineNumber = 1;
          }
          else
          {
                    lineNumber = 2;
          }

          return lineNumber;
  }