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Provided Code

public class WordPairList { private ArrayList allPairs; public WordPairList(String[] words) { } public int numMatches() { } }

Part A — 5 Points

Write the WordPairList constructor: initialize allPairs, add WordPair(words[i], words[j]) for all valid i < j.

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public WordPairList(String[] words)
{
    allPairs = new ArrayList();
    for (int i = 0; i < words.length; i++)
    {
        for (int j = i + 1; j < words.length; j++)
        {
            allPairs.add(new WordPair(words[i], words[j]));
        }
    }
}

Part B — 4 Points

Write numMatches: return the count of WordPair objects where getFirst().equals(getSecond()).

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public int numMatches()
{
    int count = 0;
    for (WordPair wp : allPairs)
    {
        if (wp.getFirst().equals(wp.getSecond()))
        {
            count++;
        }
    }
    return count;
}

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