/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
			  char [][] convert =  {   
              {},             // 0
	          {'A','B','C'},  // 1
	          {'D','E','F'},  // 2
	          {'G','H','I'},  // 3
	          {'J','K','L'},  // 4
	          {'M','N','O'},  // 5
	          {'P','R','S'},  // 6
	          {'T','U','V'},  // 7
	          {'W','X','Y'}   // 8
	      };
 
	  // Sequence of keys to be pressed. In this case the pressed keys are
	  // [ABC], [DEF], [GHI]
	  int[] sequence = new int[] {1, 2, 3};
 
	  // List for storing the results of each level.
	  List<List<String>> results = new ArrayList<>();
 
	  for(int i=0; i<sequence.length; i++){
 
		  // Results of this level
		  List<String> words = new ArrayList<>();
		  results.add(words);
 
		  List<String> prevLevelWords;
		  if(i==0){
			  prevLevelWords = Collections.singletonList("");
		  } else {
			  prevLevelWords = results.get(i-1);
		  }
 
      char[] thisLevelChars = convert[sequence[i]];
 
      if(thisLevelChars.length == 0){
        words.addAll(prevLevelWords);
      } else {
        for(String word : prevLevelWords){
          for(char ch : convert[sequence[i]]){
            words.add(word + ch);
          }
        }
      }
	  }
 
	  List<String> finalResult = results.get(sequence.length-1);
 
	  for(String word : finalResult) {
		  System.out.println(word);
	  }
 
	}
}

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