Compilare: main.cpp: In function 'void dfs(int)': main.cpp:30:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int t=0;t<G[i].size();t++) ~^~~~~~~~~~~~ main.cpp: In function 'void dfsgt(int)': main.cpp:42:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int t=0;t<GT[i].size();t++) ~^~~~~~~~~~~~~ main.cpp: In function 'void grade()': main.cpp:53:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int t=0;t<G[i].size();t++) ~^~~~~~~~~~~~