C++ Primer, Fifth Edition

3.3.1. Defining and Initializing vectors

As with any class type, the vector template controls how we define and initialize vectors. Table 3.4 (p. 99) lists the most common ways to define vectors.

Table 3.4. Ways to Initialize a vector

We can default initialize a vector (§ 2.2.1, p. 44), which creates an empty vector of the specified type:

vector<string> svec; // default initialization; svec has no elements

It might seem that an empty vector would be of little use. However, as we’ll see shortly, we can (efficiently) add elements to a vector at ...