fastest way to get string size in c++ code example

Example 1: c++ string size

// C++ string size
str.length();
str.size();			// synonym

Example 2: c++ string size

// string::size
#include <iostream>
#include <string>

int main ()
{
  std::string str ("Test string");
  std::cout << "The size of str is " << str.size() << " bytes.\n";
  return 0;
}