Compilare: user.cpp: In function ‘void DFS(int)’: user.cpp:38:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<graph[x].size();++i) ^ user.cpp: In function ‘int main()’: user.cpp:75:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<sol[i].size();++j) ^