If you need to concatenate variables of different types to form a string, use a stringstream object. The header contains the declarations of the stringstream family of classes. Using its overloaded << operators, stringstream will convert variables of built-in types such as int, double and char * into a string and store the result in its internal buffer. To extract the resulting string, use the >> operator:

  #include void concat(std::string &result){ long x = 1000; double y = 5.5.; std::stringstream s; s << "(" << x << "," << y << ")"; s>>result; // result is now "(1000,5.5)"}