2021 FRQ 3

5 min read

FRQ Question
- Code Runner Challenge
Part (a) - addMembers
Scoring Guidelines Part (a)
Part (b) - removeMembers
- Example
Scoring Guidelines Part (b)

FRQ Question

A high school club maintains information about its members in a MemberInfo object. A MemberInfo object stores a club member’s name, year of graduation, and whether or not the club member is in good standing. A member who is in good standing has fulfilled all the responsibilities of club membership.

A partial declaration of the MemberInfo class is shown below:

Code Runner Challenge

Club Members ArrayList Management

View IPYNB Source

public class MemberInfo {
    public MemberInfo(String name, int gradYear, boolean hasGoodStanding) { }
    public int getGradYear() { }
    public boolean inGoodStanding() { }
}

Lines: 1 Characters: 0

Output

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The ClubMembers class maintains a list of current club members:

public class ClubMembers {
    private ArrayList<MemberInfo> memberList;
    public void addMembers(String[] names, int gradYear) { }
    public ArrayList<MemberInfo> removeMembers(int year) { }
}

// CODE_RUNNER: Club Members ArrayList Management

import java.util.ArrayList;

class MemberInfo {
    private String name;
    private int gradYear;
    private boolean hasGoodStanding;
    
    public MemberInfo(String name, int gradYear, boolean hasGoodStanding) {
        this.name = name;
        this.gradYear = gradYear;
        this.hasGoodStanding = hasGoodStanding;
    }
    
    public int getGradYear() { return gradYear; }
    public boolean inGoodStanding() { return hasGoodStanding; }
    public String toString() { return name + " (" + gradYear + ") - " + (hasGoodStanding ? "Good" : "Bad"); }
}

class ClubMembers {
    private ArrayList<MemberInfo> memberList;
    
    public ClubMembers() {
        memberList = new ArrayList<>();
    }
    
    public void addMembers(String[] names, int gradYear) {
        // PART (a): Implement this method
        for (String name : names) {
            memberList.add(new MemberInfo(name, gradYear, true));
        }
    }
    
    public ArrayList<MemberInfo> removeMembers(int year) {
        // PART (b): Implement this method
        ArrayList<MemberInfo> graduated = new ArrayList<>();
        
        for (int i = memberList.size() - 1; i >= 0; i--) {
            MemberInfo member = memberList.get(i);
            if (member.getGradYear() <= year) {
                if (member.inGoodStanding()) {
                    graduated.add(member);
                }
                memberList.remove(i);
            }
        }
        
        return graduated;
    }
    
    public void printMembers() {
        System.out.println("Current Members:");
        for (MemberInfo m : memberList) {
            System.out.println("  " + m);
        }
    }
}

public class Main {
    public static void main(String[] args) {
        ClubMembers club = new ClubMembers();
        
        // Add members
        String[] names1 = {"FOX, STEVE", "XIN, MICHAEL"};
        club.addMembers(names1, 2018);
        
        String[] names2 = {"SMITH, JANE", "GARCIA, MARIA"};
        club.addMembers(names2, 2019);
        
        System.out.println("Before removeMembers(2018):");
        club.printMembers();
        
        ArrayList<MemberInfo> graduated = club.removeMembers(2018);
        
        System.out.println("\nAfter removeMembers(2018):");
        club.printMembers();
        
        System.out.println("\nGraduated in good standing:");
        for (MemberInfo m : graduated) {
            System.out.println("  " + m);
        }
    }
}

Main.main(null);

Part (a) - addMembers

Write the ClubMembers method addMembers, which takes two parameters:

A String array containing the names of new club members to be added
The graduation year of all the new club members

The method adds the new members to the memberList instance variable. The names can be added in any order. All members added are initially in good standing and share the same graduation year.

public void addMembers(String[] names, int gradYear)

Scoring Guidelines Part (a)

Criterion	Decision Rules	Points
Accesses all elements of names (no bounds errors)	Responses will not earn the point if they fail to access elements of the array, even if loop bounds are correct	1
Instantiates a MemberInfo object with name from array, provided year, and good standing		1
Adds MemberInfo objects to memberList (in the context of a loop)	Responses can earn the point even if they instantiate MemberInfo objects incorrectly	1
Total for part (a)		3

Part (b) - removeMembers

Write the ClubMembers method removeMembers, which takes the following actions:

Returns a list of all students who have graduated and are in good standing
- A member has graduated if their graduation year is less than or equal to the method’s year parameter
- If no members meet these criteria, an empty list is returned
Removes from memberList all members who have graduated, regardless of whether or not they are in good standing

Example

Given the following memberList before calling removeMembers(2018):

Name	Year	Good Standing
SMITH, JANE	2019	false
FOX, STEVE	2018	true
XIN, MICHAEL	2017	false
GARCIA, MARIA	2020	true

After removeMembers(2018):

public ArrayList<MemberInfo> removeMembers(int year)

Scoring Guidelines Part (b)

Criterion	Decision Rules	Points
Declares and initializes an ArrayList of MemberInfo objects	Responses will not earn the point if they initialize the variable with a reference to the instance variable	1
Accesses all elements of memberList for potential removal (no bounds errors)	Responses will not earn the point if they: fail to use `get(i)`, fail to attempt to remove an element, skip an element, or throw an exception due to removing	1
Calls getGradYear or inGoodStanding	Responses will not earn the point if they ever include parameters in either method call or call either method on an object other than MemberInfo	1
Distinguishes any three cases, based on graduation status and standing	Responses will not earn the point if they fail to behave differently in all three cases	1
Identifies graduating members	Responses will not earn the point if they confuse `<` and `<=` in the comparison	1
Removes appropriate members from memberList and adds appropriate members to the ArrayList to be returned	Responses will not earn the point if they fail to declare an ArrayList to return or fail to distinguish the correct three cases (with exception of confusing `<` and `<=` in comparison)	1
Total for part (b)		6
Total for question 3		9

Computer Science A