C++ Primer, Fifth Edition

9.5.2. Other Ways to Change a string

The string type supports the sequential container assignment operators and the assign, insert, and erase operations (§ 9.2.5, p. 337, § 9.3.1, p. 342, and § 9.3.3, p. 348). It also defines additional versions of insert and erase.

In addition to the versions of insert and erase that take iterators, string provides versions that take an index. The index indicates the starting element to erase or the position before which to insert the given values:

s.insert(s.size(), 5, '!'); // insert five exclamation points at the end of ss.erase(s.size() - 5, 5);   // erase the last five characters from s

The string library ...