ap computer science a 2021 free response answers code example

Example 1: 2019 ap computer science free response answers

// Part A
public ArrayList<String> getDelimitersList(String[] tokens) {
	ArrayList<String> out = new ArrayList<>();
	for (String t: tokens) {
		if (t.equals(openDel) || t.equals(closeDel))
			out.add(t); 
	}
	return out; 
}

// Part B
public boolean isBalanced(ArrayList<String> delimiters) {
	int open = 0;
	int close = 0;
	for (String d: delimiters) {
		if (d.equals(openDel))
			open++;
		else if (d.equals(closeDel))
			close++;
		
		if (close > open)
			return false;
	}
	return open == close; 
}

Example 2: 2019 ap computer science free response answers

public class StepTracker {
	private int days;
	private int activeDays;
	private int totalSteps;
	private int minActive;
	
	public StepTracker(int m) {
		minActive = m;
		days = 0;
		activeDays = 0;
		totalSteps = 0; 
	}
	
	public void addDailySteps(int steps) {
		days++;
		totalSteps += steps;
		if (steps >= minActive) {
			activeDays++;
		}
	}
	
	public int activeDays() {
		return activeDays; 
	}
	
	public double averageSteps() {
		if (days == 0) {
			return 0.0; 
		}
		return (double)totalSteps / days; 
	}
}