Compilare: user.cpp: In function ‘void read_input_lee()’: user.cpp:71:9: warning: unused variable ‘s’ [-Wunused-variable] int s = 0; ^ user.cpp: In function ‘void lee_all()’: user.cpp:126:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i <= v2.size() - 1; ++i) { ^ user.cpp: In function ‘bool isOk2(int, int)’: user.cpp:38:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.cpp: In function ‘bool isOk3(int, int)’: user.cpp:49:1: warning: control reaches end of non-void function [-Wreturn-type] } ^