Sign is #2 from the from the 2023 AP Computer Science A Free Response problems.

https://apcentral.collegeboard.org/media/pdf/ap23-frq-comp-sci-a.pdf

Sign class

public class Sign
{
    private String message;
    private int lineWidth;
    
    public Sign(String message, int lineWidth)
    {
        this.message = message;
        this.lineWidth = lineWidth;
    }
    
    public int numberOfLines()
    {
        int lines = message.length() / lineWidth;
        
        if(message.length() % lineWidth > 0)
            lines++;
        
        return lines;
    }
    
    public String getLines()
    {
        if(message.length() == 0)
            return null;
        
        String lines = "";
        String messageRemaining = message;
        
        while(messageRemaining.length() > lineWidth)
        {
            lines += messageRemaining.substring(0, lineWidth);
            lines += ";";
            messageRemaining = messageRemaining.substring(lineWidth);
        }
        
        lines += messageRemaining;
        
        return lines;
    }
}

As an alternative to storing message and lineWidth, it is possible to store the number of lines and the String representing the formatted lines.

See Class writing order for a technique to respond to AP CS FR that request an entire class.

See Strings on the AP CS A Exam for detailed examples of calls to substring.

Java files with test code

TwoTest.java includes JUnit 5 test code with the examples from the problem. See Running JUnit 5 tests.

Sign.java
TwoTest.java

2023 AP CS Exam Free Response Solutions

• AppointmentBook Free Response Solution
• WeatherData Free Response Solution
• BoxOfCandy Free Response Solution

Help & comments

Get help from AP CS Tutor Brandon Horn

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