Compilare: user.cpp: In function ‘void ca()’: user.cpp:5:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] #define as a.size() ^ user.cpp:44:26: note: in expansion of macro ‘as’ for (int i=0,q=as; i<as; i++) ^ user.cpp:44:18: warning: unused variable ‘q’ [-Wunused-variable] for (int i=0,q=as; i<as; i++) ^ user.cpp: At global scope: user.cpp:87:6: warning: ISO C++ forbids declaration of ‘main’ with no type [-Wreturn-type] main() ^