2. 코드

public class NumberSum {
 
  public static void main(String[] args) {
    NumberSum ns = new NumberSum();
    System.out.println("result=" + ns.get(153));
    System.out.println("result=" + ns.get(348));
  }
 
  private int get(int i) {
    int result = 0;
 
    while ( i > 0 ) {
      result += i % 10;
      i /= 10;
    }
 
    return result;
  }
}