Compilare: user.cpp: In function ‘void DFS1(int)’: user.cpp:18:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < v[nod].size(); i++) ~~^~~~~~~~~~~~~~~ user.cpp: In function ‘void DFS2(int)’: user.cpp:28:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < v_back[nod].size(); i++) ~~^~~~~~~~~~~~~~~~~~~~ user.cpp: In function ‘int main()’: user.cpp:55:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < sol[i].size(); j++) ~~^~~~~~~~~~~~~~~