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Java Java Objects Creating the MVP Conference Registration Assistant

Enyang Mercy
PLUS
Enyang Mercy
Courses Plus Student 2,339 Points

getLineNumber return 1

Please help!! i don't know how to go about this challenge trying to fix the code but seems something isnt right

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

     */
    lastName.CharAt(3);
    if('A' < 'M') {
      return 1;
  }
    if ('N' > 'Z') {
      return 2;
}
    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");
  }

}

2 Answers

Yanuar Prakoso
Yanuar Prakoso
15,196 Points

Hi Enyang

First of all the task asks you to group some people according to the first letter (index 0) of their lastName. Therefore you should use lastName.charAt(0).

Then you need to fix your IF statement. In the other java file it is stated that you can compare characters like if it was an integer. Thus 'a' will be less than 'n' and 'z' will always higher than 'a'. You can use it to check if(lastName.charAt(0) is lower than 'n'). IF this is true then you will group it to lineNumber = 1, ELSE it will be lineNumber = 2.

I try your challenge and came up with this code:

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

     */
    if(lastName.toLowerCase().charAt(0) < 'n'){
      lineNumber = 1;
    }else {
      lineNumber = 2;
    }
    return lineNumber;
  }

}

I hope this can help a little.