[LeetCode] Problem 500 - Keyboard Row

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Given a List of words, return the words that can be typed using letters of alphabet on only one row’s of American keyboard like the image below.

exFfUK.png

Example

Input: [“Hello”, “Alaska”, “Dad”, “Peace”]

Output: [“Alaska”, “Dad”]

Note

  1. You may use one character in the keyboard more than once.
  2. You may assume the input string will only contain letters of alphabet.

Code

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private String[] rows = {"qwertyuiop", "asdfghjkl", "zxcvbnm"};

public String[] findWords(String[] words) {
    List<String> result = new ArrayList<>();

    for (String word : words) {
        for (String row : rows) {
            if (check(word.toLowerCase(), row)) {
                result.add(word);
                break;
            }
        }
    }
    
    return result.toArray(new String[result.size()]);
}

private boolean check(String word, String row) {
    for (char ch : word.toCharArray()) {
        if (row.indexOf(ch) == -1)
            return false;
    }

    return true;
}