string s; cin>>s; suppose s = "stackoverflow"
now if we access s[3], it should give out 'c'
will s[3] be 'c' or "c"?
as in will it be a char data type or string data type?
- 2You can always check the documentation to kow that.πάντα ῥεῖ– πάντα ῥεῖ2017-06-11 11:25:36 +00:00Commented Jun 11, 2017 at 11:25
Add a comment |
3 Answers
std::string is not a built-in type, so operator [] in s[3] is a call to a member function defining this operator in the string template.
You can find the type by looking up the reference page for operator []:
Returns a reference to the character at specified location pos.
To look up the type reference and const_reference from the documentation see "member types" section of std::basic_string<CharT> template.
If you are looking for std::string of length 1 starting at location 3, use substr instead:
s.substr(3, 1); // This produces std::string containing "c" answered Jun 11, 2017 at 11:23
Sergey Kalinichenko
729k85 gold badges1.2k silver badges1.6k bronze badges
2 Comments
aschepler
Perhaps you could also explain how to look up the return type "
reference" in the parent page and untangle the template usage to finally get "char&".
Sergey Kalinichenko
@aschepler Thanks!
It returns reference to the character as the operator [] is overloaded for std::string
char& operator[] (size_t pos); const char& operator[] (size_t pos) const; will s[3] be 'c' or "c"?
Character 'c', not string "c".
Comments
It is easiest to remember that std::string is not a native type like char is, but a wrapper class that contains an array of chars to form a string.
std::string simply overloads the C array operator [] to return the char at a given index, hence:
will
s[3]be'c'or"c"?Answer:
'c'
