Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:11:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int i = 0; i < v[nod].size(); i++ ){ ^ user.cpp: In function ‘int main()’: user.cpp:33:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int i = 0; i < v[1].size(); i++ ){ ^ user.cpp:42:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int j = 0; j < v[i].size(); j++ ){ ^