class Main{
  String g(int n, int depth){     // Recursive method with 2 int parameters & String return-type
    int remainder = n % depth;    //  The current recursive remainder
    if(depth < n){                //  If we aren't done with the number yet:
      int nextDepth = depth * 10; //   Go to the next depth (of the power of 10)
      int nextN = n - remainder;  //   Remove the remainder from the input `n`
                                  //   Do a recursive call with these next `n` and `depth`
      String resultRecursiveCall = g(nextN, nextDepth);
      if(remainder != 0){         //   If the remainder was not 0:
                                  //    Append a " + " and this remainder to the result
        resultRecursiveCall += " + " + remainder;
      }
      return resultRecursiveCall; //   And return the result
    } else{                       //  Else:
      return Integer.toString(n); //   Simply return input `n` as result
    }
  }
 
  String f(int n){                // Second method so we can accept just integer `n`
    return g(n, 1);               //  Which will call the recursive call with parameters `n` and 1
  }
 
  public static void main(String[] a){
    Main m = new Main();
    m.test(9);
    m.test(10);
    m.test(12);
    m.test(101);
    m.test(123);
    m.test(1024);
    m.test(70304);
  }
 
  void test(int input){
    System.out.println(f(input));
  }
}

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