Compilare: user.cpp: In function ‘void dfsrel(int)’: user.cpp:14:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v[x].size();i++) ~^~~~~~~~~~~~ user.cpp: In function ‘void dfs(int)’: user.cpp:25:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<v[x].size();i++) ~^~~~~~~~~~~~