public class VowelExpert {
    
    /** Given a list of target characters, find the (index of the)
     * first char in a word which is one of the targets.
     * @param word The word to find a vowel in.
     * @param target the list of characters we are looking for.
     * @return the index of the first target char in `word`, or (if no
     *  targets occurs) the first index past the end of the String.
     */    
    int firstCharFrom( String word, String target ) {
        int i = 0;
        boolean seenATargetChar = false;
        while (i < word.length() && !seenATargetChar) {
            if (target.contains(word.substring(i,i+1))) {
                seenATargetChar = true;
                }
                ++i;
            }
        return i;
        }
    
    /** Find the position of the letter 'A' in a word.
     * @param word The word to find a vowel in.
     * @return the index of the first letter 'A' in `word` (upper or lower
     * case), or (if no 'A' occurs) the first index past the end of the String.
     */    
    public int firstA( String word ) {
        return firstCharFrom( word, "Aa" );
        }
        
    /** Find the position of the first vowel in a word.
     * @param word The word to find a vowel in.
     * @return the index of the first vowel in `word`, or (if no
     *  vowel occurs) the first index past the end of the String.
     */    
    public int firstVowel( String word ) {
        return firstCharFrom( word, VOWELS.toLowerCase()+VOWELS.toUpperCase() );
        }        
        
        
    /** Translate a word to Pig Latin.
     * @param word The word to translate.
     * @return `word` translated into (some dialect of) Pig Latin.
     */   
    public String toPigLatin( String word ) {
        int firstV = firstVowel(word);
        int lastIndex = word.length();
        String firstPart = word.substring(0,firstV);
        String rest = word.substring(firstV, lastIndex);
        return rest + firstPart + "ay";
        }
        
        

        
    private static final String VOWELS = "AE10U";
        
    }