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Provided Code

public class WordMatch
{
    private String secret;
    public WordMatch(String word) { /* not shown */ }
    /** Returns count of overlapping occurrences of guess in secret, multiplied by guess.length()^2. */
    public int scoreGuess(String guess) { /* to be implemented in part (a) */ }
    /** Returns the better of two guesses: higher score wins; if tied, alphabetically greater wins. */
    public String findBetterGuess(String guess1, String guess2) { /* to be implemented in part (b) */ }
}

Part A — 4 Points

Write scoreGuess: count overlapping occurrences of guess in secret and return the count multiplied by guess.length() * guess.length().

Write Your Solution

Check Answer Clear

public int scoreGuess(String guess)
{
    int count = 0;
    int gLen = guess.length();
    for (int i = 0; i <= secret.length() - gLen; i++)
    {
        if (secret.substring(i, i + gLen).equals(guess))
        {
            count++;
        }
    }
    return count * gLen * gLen;
}

Part B — 5 Points

Write findBetterGuess: return the guess with the higher score. On a tie, return the alphabetically greater guess. Must use scoreGuess.

Write Your Solution

Check Answer Clear

public String findBetterGuess(String guess1, String guess2)
{
    int score1 = scoreGuess(guess1);
    int score2 = scoreGuess(guess2);
    if (score1 > score2) {
        return guess1;
    }
    if (score2 > score1) {
        return guess2;
    }
    // tie: return alphabetically greater
    if (guess1.compareTo(guess2) > 0) {
        return guess1;
    }
    return guess2;
}

Common Mistakes to Avoid

for (int i = 0; i < secret.length(); i++)  // too far!

for (int i = 0; i <= secret.length() - gLen; i++)

if (secret.substring(i, i + gLen) == guess)

if (secret.substring(i, i + gLen).equals(guess))

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