Delimiters free response answer 2019

Delimiters is #3 from the from the 2019 AP Computer Science A Free Response problems.

https://apcentral.collegeboard.org/pdf/ap19-frq-computer-science-a.pdf?course=ap-computer-science-a

Part (a) getDelimitersList method

public ArrayList<String> getDelimitersList(String[] tokens)
{
    ArrayList<String> delimiters = new ArrayList<String>();

    for(String t : tokens)
        if(t.equals(openDel) || t.equals(closeDel))
            delimiters.add(t);

    return delimiters;
}

Part (b) isBalanced method

public boolean isBalanced(ArrayList<String> delimiters)
{
    int numOpen = 0, numClosed = 0;

    for(String d : delimiters)
    {
        if(d.equals(openDel))
            numOpen++;

        if(d.equals(closeDel))
            numClosed++;

        if(numClosed > numOpen)
            return false;
    }

    return numOpen == numClosed;
}

2019 AP CS Exam Free Response Solutions

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