public class ImprovedDigitsRecursion
{
  public static void main(String args[]){
    int x = 7312;
    
    System.out.print(x+" = ");
    printInteger(x, 0);
    System.out.println("");
  }
  
  static void printInteger(int x, int level){
    if(x == 0)
      return;
    
    printInteger(x / 10, level+1);

    if(level >= 2 && x % 10 != 0){
      printDigit(x % 10);
      printOrder(level);
    }else if(level == 1){
      if(x % 10 >= 2)
        printSecond(x % 10);
    }else{
      if(x % 100 < 20)
        printTeens(x % 100);
      else
        printDigit(x % 10);
    }
  }
  
  static void printOrder(int x){
    if(x == 3)
      System.out.print("thousand ");
    else if(x == 2)
      System.out.print("hundred ");
    else
      System.out.print("* ");
  }

  static void printTeens(int x){
    if(x < 10){
      printDigit(x);
      return;
    }
    switch(x){
        case 10:
          System.out.print("ten ");
          break;
        case 11:
          System.out.print("eleven ");
          break;
        case 12:
          System.out.print("twelve ");
          break;
        case 13:
          System.out.print("thirteen ");
          break;
        case 14:
          System.out.print("fourteen ");
          break;
        case 15:
          System.out.print("fifteen ");
          break;
        case 16:
          System.out.print("sixteen ");
          break;
        case 17:
          System.out.print("seventeen ");
          break;
        case 18:
          System.out.print("eighteen ");
          break;
        case 19:
          System.out.print("nineteen ");
          break;
        default:
          System.out.print("* ");
     }
  }

  static void printSecond(int x){
    switch(x){
        case 0:
          //System.out.print("zero ");
          break;
        case 1:
          System.out.print("* ");
          break;
        case 2:
          System.out.print("twenty ");
          break;
        case 3:
          System.out.print("thirty ");
          break;
        case 4:
          System.out.print("forty ");
          break;
        case 5:
          System.out.print("fifty ");
          break;
        case 6:
          System.out.print("sixty ");
          break;
        case 7:
          System.out.print("seventy ");
          break;
        case 8:
          System.out.print("eighty ");
          break;
        case 9:
          System.out.print("ninety ");
          break;
        default:
          System.out.print("* ");
     }
  }

  static void printDigit(int x){
    switch(x){
        case 0:
          //System.out.print("zero ");
          break;
        case 1:
          System.out.print("one ");
          break;
        case 2:
          System.out.print("two ");
          break;
        case 3:
          System.out.print("three ");
          break;
        case 4:
          System.out.print("four ");
          break;
        case 5:
          System.out.print("five ");
          break;
        case 6:
          System.out.print("six ");
          break;
        case 7:
          System.out.print("seven ");
          break;
        case 8:
          System.out.print("eight ");
          break;
        case 9:
          System.out.print("nine ");
          break;
        default:
          System.out.print("* ");
     }
   }
}