public static int addition (int a , int b)
  { 
      
      if (b == 0)
       {  
          
          return a;
          
       }
       else
      { 
          a++;
          b--;
          return addition(a,b);
       }
      
     
      
  }
    public static int multiplikation(int a, int b) 
  {
      
      if (a == 0 || b == 0) 
      {
          return 0;
      } 

        else 
        {
            return addition(a, multiplikation(a, b - 1));
        }