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Java Java Objects Creating the MVP Conference Registration Assistant

Joakim Sjöstedt
Joakim Sjöstedt
1,975 Points

Help with ConferenceRegistrationAssistance

Hi! I have a really hard time understanding what to do in this exercise. Something like if(lastName[0].indexOf(a-m)) return 1; else return 2;

terrible coding, I know, but I'm at a loss...

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;
    if(lastName[0].indexOf('a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm'))
       return 1;
       else
       return 2;
    /*
      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");
  }

}

5 Answers

Joakim Sjöstedt
Joakim Sjöstedt
1,975 Points

Oh, forgot to write the challange: 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.

Kayondo Martin
Kayondo Martin
7,481 Points

how about doing this

String Sequence = "abcdefghilklm"; if(Sequence.contains(lastName.CharAt(0)+"") return 1; else return 2;

......

Joakim Sjöstedt
Joakim Sjöstedt
1,975 Points

Hmm, doesn't seem to work. Can't find symbol...

Kayondo Martin
Kayondo Martin
7,481 Points

I guess you missed a spelling or something of the kind, I tried the challenge and it worked.

try this

String sequence = "ABCDEFGHIJKLM";
if(sequence.contains((lastName.charAt(0)+"").toUpperCase()))
{
lineNumber = 1;
}else
{
lineNumber = 2;
}

That should do it!

Joakim Sjöstedt
Joakim Sjöstedt
1,975 Points

Alright man, thanks a lot, it worked! Think I missed setting the lineNumber at the end.

Challange seems a bit too hard at this early point. Don't even remember having learned this type of code before...

Anyway thanks again for your time and help :)

shu Chan
shu Chan
2,951 Points

Why the + "" and .toUpperCase ?