c++ primer 练习

int ()
{
   int a,b;
   std::cin >> a >> b ;
    if (a>b)
    {
       int val = b;
       while (val <= a)
        {
           std::cout << val <<std::endl;
           ++val;
      }
   }
   if (a<b)
    {
       int val = a;
       while (val <= b)
        {
           std::cout << val <<std::endl;
           ++val;
      }
   }
   else
   {
       std::cout << a <<std::endl;
 }
   return 0;
}