Compilare: user.cpp: In function ‘int main()’: user.cpp:114:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0 ; i < v[act].size() ; ++i){ ^ user.cpp:137:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0 ; i < sol.size() ; ++i) ^