Write a Java program to input a sentence that must terminate with a full stop or a question mark or an exclamation mark. Now generate a new sentence by converting each word of the original sentence to piglatin.

The following rules are to be followed to convert a word into piglatin:

• For words that start with a consonant: Move the initial consonant cluster to the end of the word and add “AY”. Example: WELCOME becomes ELCOMEWAY.
• For words that start with a vowel: Simply add “AY” to the end of the word. Example: APPLE becomes APPLEAY.

import java.util.Scanner;
class Piglatin{
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        System.out.print("Enter the sentence: ");
        String s = in.nextLine().toUpperCase();
        if(s.length() == 0){
            System.out.println("INVALID SENTENCE");
            return;
        }
        char last = s.charAt(s.length() - 1);
        if(".?!".indexOf(last) == -1){
            System.out.println("INVALID SENTENCE");
            return;
        }
        String p = "";
        String word = "";
        for(int i = 0; i < s.length(); i++){
            char ch = s.charAt(i);
            if(Character.isLetterOrDigit(ch))
                word += ch;
            else{
                ch = s.charAt(i);
                if(word.length() > 0)
                    p += convert(word) + ch;
                else
                    p += ch;
                word = "";
            }
        }
        System.out.println(p);
    }
    public static String convert(String w){
        int pos = 0;
        for(int i = 0; i < w.length(); i++){
            char ch = w.charAt(i);
            if("AEIOU".indexOf(ch) >= 0){
                pos = i;
                break;
            }
        }
        String p = w.substring(pos, w.length());
        p += w.substring(0, pos) + "AY";
        return p;
    }
}