std::basic_string::size, std::basic_string::length
From cppreference.com
                    
                                        
                    < cpp | string | basic string
                    
                                                            
                    |   size_type size() const; 
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|   size_type length() const; 
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Returns the number of characters in the string, i.e. std::distance(begin(), end()).
Contents | 
[edit] Parameters
(none)
[edit] Return value
The number of characters in the string.
[edit] Complexity
Constant
[edit] See also
|    checks whether the string is empty   (public member function)  | 
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|    returns the maximum number of characters   (public member function)  | 
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