std 3a 3astring 28size t 2c char 29 constructor 3a

1string (const string& str, size_t pos, size_t len = npos);
2

1string();
2

1string (const char* s, size_t n);
2

1string (const string& str);
2

1string (size_t n, char c);
2

1template <class InputIterator>
2  string  (InputIterator first, InputIterator last);
3