Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:1:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] #define REP(a,b) for(int a=0; a<(b); ++a) ^ user.cpp:74:5: note: in expansion of macro ‘REP’ REP(i,G[n].size()) ^ user.cpp:1:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] #define REP(a,b) for(int a=0; a<(b); ++a) ^ user.cpp:106:5: note: in expansion of macro ‘REP’ REP(i, G[n].size()) ^