Hi I am making a C++ program but i got some problem here. I have one header file and one source file Slover.hpp and Slover.cpp the content of the Slover.hpp is #ifndef SLOVER_HPP_ #define SLOVER_HPP_ #include <iostream> #include <cstdlib> #include <ctime> #include <math.h> #include <iomanip> #include <string> #include <vector> using namespace std; #include "Game.hpp" class Slover{ private: typedef struct Guess { vector <char> guessPuzzle; int CorrectPosition; int CorrectColor; }; vector <Guess> guesses; public: Slover(); ~Slover(); bool Guess (const Game* game, Guess &guessPuzzle); }; and the Slover.cpp file is: using namespace std; #include "Slover.hpp" Slover(){ } ~Slover(){ } bool Slover::Guess (const Game* game, Guess &guessPuzzle){ //do something here return true; I got the error message: error: prototype for `bool Slover::Guess(const Game*, int&)' does not match any in class `Slover' Can you please tell me what mistake that i have made there? And how can i fix this? I am quite new to C++ so please forgive if the question is not appropriate. Thanks you very much -- View this message in context: http://www.nabble.com/Hi-can-you-please-help-me-tf3284243.html#a9135386 Sent from the gcc - Help mailing list archive at Nabble.com.