Compilare: user.cpp: In function ‘bool subs(std::string, std::string)’: user.cpp:5:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] #define nope string::npos ^ user.cpp:23:14: note: in expansion of macro ‘nope’ while(p!=nope&&i<sub.size()) ^ user.cpp:23:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(p!=nope&&i<sub.size()) ^ user.cpp:5:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] #define nope string::npos ^ user.cpp:26:15: note: in expansion of macro ‘nope’ if(p==nope)break; ^ user.cpp:5:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] #define nope string::npos ^ user.cpp:30:17: note: in expansion of macro ‘nope’ return !(p==nope); ^