int f(int a)
{
  if (a%3==0)
    return 0;
  return 1+f(a-1)
}

int f(int b, int c)
{
  if(b>c)
    if(b%c==0)
      return f(b+b/c,c);
      else
        return 1+f(b+b%c,c);
  return b;
}

int f(int x, int d)
{
  while(x>0)
  {
    if(x==d)
      return 1;
    if(x%d==0)
      return 1+ f(x/d, d+1)
    return f(x-1, d);
  }
  return 0;
}

void f(int x, int &y)
{
  if(x==y) cout<<x<<y;
    else
    {x++; y--; f(x,y); cout<<x<<y}
}