Provided Code

public class StringFormatter
{
    public static int totalLetters(ArrayList wordList)
    { /* to be implemented in part (a) */ }

    public static int leftoverSpaces(ArrayList wordList, int formattedLen)
    { /* to be implemented in part (b) */ }

    public static String format(ArrayList wordList, int formattedLen)
    { /* to be implemented in part (c) */ }
}

Part A — totalLetters (2 Points)

Write totalLetters(). Return the total number of characters across all words in wordList.

Check Answer Clear

public static int totalLetters(ArrayList wordList)
{
    int total = 0;
    for (String word : wordList)
    {
        total += word.length();
    }
    return total;
}

Part B — leftoverSpaces (2 Points)

Write leftoverSpaces(). Return the number of spaces that must be distributed across the gaps between words to reach formattedLen total length.

Check Answer Clear

public static int leftoverSpaces(ArrayList wordList, int formattedLen)
{
    return formattedLen - totalLetters(wordList);
}

Part C — format (5 Points)

Write format(). Distribute leftoverSpaces() evenly across the gaps between words (wordList.size()-1 gaps). The leftmost gaps receive one extra space each when the total does not divide evenly.

Check Answer Clear

public static String format(ArrayList wordList, int formattedLen)
{
    int numGaps = wordList.size() - 1;
    int totalSpaces = leftoverSpaces(wordList, formattedLen);
    int baseSpaces = totalSpaces / numGaps;
    int extraSpaces = totalSpaces % numGaps;

    String result = wordList.get(0);

    for (int i = 1; i < wordList.size(); i++)
    {
        int spaces = baseSpaces + (i - 1 < extraSpaces ? 1 : 0);
        for (int s = 0; s < spaces; s++)
        {
            result += " ";
        }
        result += wordList.get(i);
    }

    return result;
}

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