Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:39:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < V[a].size(); i++) ^ user.cpp:8:11: warning: unused variable ‘first’ [-Wunused-variable] #define x first ^ user.cpp:42:13: note: in expansion of macro ‘x’ int x = val / 1030; ^ user.cpp:9:11: warning: unused variable ‘second’ [-Wunused-variable] #define y second ^ user.cpp:43:13: note: in expansion of macro ‘y’ int y = val % 1030; ^