Print Keypad Combinations... in JAVA

 

import java.util.*;

public class Recursion2 {

public static String[] keybopard = { ".", "abc", "def", "ghi", "jkl", "mno", "pqrs", "tuv", "wxyz" };

    public static void printCombo(String str, int idx, String combination) {

        if (idx == str.length()) {

            System.out.println(combination);

            return;

        }

        char currChar = str.charAt(idx);

        String mapping = keybopard[currChar - '0'];

        for (int i = 0; i < mapping.length(); i++) {

            printCombo(str, idx + 1, combination + mapping.charAt(i));

        }

    }

 public static void main(String[] args) {

        String str = "23";

       

         printCombo(str, 0, "");

    }

}

OUTPUT :

dg

dh di eg eh ei fg fh fi