Exceptional C++ Style 40 New Engineering Puzzles, Programming Problems, and Solutions

Chapter 29. Is It Initialization?

Difficulty: 3

Most people know the famous quote: “What if they gave a war and no one came?” This time, we consider the question: “What if we initialized an object and nothing happened?” As Scarlett might say in such a situation: “This isn't right, I do declare!”

Assume that the relevant standard headers are included and that the appropriate using-declarations are made.

JG Question

1. What does the following code do?

   deque<string> coll1;
   
   copy(istream_iterator<string>(cin),
        istream_iterator<string>(),
        back_inserter(coll1));
   

Guru Question

1. What does the following code do?

   deque<string> coll2(coll1.begin(), coll1.end());
   
   deque<string> coll3(istream_iterator<string>(cin),
    istream_iterator<string>());
   

2. What must be changed to ...