Compilare: user.cpp: In function ‘void detach(int, int)’: user.cpp:128:9: warning: variable ‘nx’ set but not used [-Wunused-but-set-variable] int nx, ny, lnk; ^ user.cpp:128:13: warning: variable ‘ny’ set but not used [-Wunused-but-set-variable] int nx, ny, lnk; ^ user.cpp: In function ‘int main()’: user.cpp:166:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < a.size(); i+= 2) ^ user.cpp:179:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < e.size(); i+= 2) ^ user.cpp:182:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < a.size(); i+= 2) ^