Compilare: user.cpp: In function ‘void af()’: user.cpp:44:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<sol.size();i++) ^ user.cpp:46:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<sol[i].size();j++) ^ user.cpp: In function ‘void biconex(int, int)’: user.cpp:56:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<a[nod].size();i++) ^