Compilare: user.cpp: In function ‘int reject(instance, config)’: user.cpp:30:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (c.size() > P.K) ^ user.cpp: In function ‘int accept(instance, config)’: user.cpp:42:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] return c.size() == P.K; ^ user.cpp: In function ‘config first(instance, config)’: user.cpp:47:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (c.size () >= P.K) ^ user.cpp: In function ‘void output(instance, config)’: user.cpp:80:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < c.size(); i++) ^