Compilare: main.cpp: In function 'void dfs(int)': main.cpp:10:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j,i=0;i<G[x].size();i++) ~^~~~~~~~~~~~ main.cpp:13:25: warning: pointer to a function used in arithmetic [-Wpointer-arith] if(!viz[j])dfs[j]; ^ main.cpp:13:25: warning: value computed is not used [-Wunused-value] if(!viz[j])dfs[j]; ~~~~~^ main.cpp:13:25: warning: statement has no effect [-Wunused-value]