Compilare: main.cpp: In function 'bool havel_hakimi(std::vector<std::pair<int, int> >, std::vector<int>*)': main.cpp:14:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(grade[i].first < -grade.size()+1 || grade[i].first > 0) main.cpp:35:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < grade.size(); ++i) ~~^~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:73:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < graf[i].size(); ++j) ~~^~~~~~~~~~~~~~~~