Compilare: user.cpp: In member function ‘graph* graph::simplify(int*, int)’: user.cpp:64:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < V[i].size(); j++) ^ user.cpp: In member function ‘void graph::do_calc(std::vector<int>&)’: user.cpp:74:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < V[i].size(); j++) { ^ user.cpp:89:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < cur_elems.size(); i++) ^ user.cpp:93:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < V[cur_elems[i]].size(); j++) { ^ user.cpp: In function ‘int main()’: user.cpp:130:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < sol.size(); i++) ^ user.cpp:137:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < sol.size(); i++) ^