Compilare: main.cpp: In function 'bool IsInList(std::vector<int>&, int)': main.cpp:17:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < a.size(); ++i) ~~^~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:45:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < exterior[i].size(); ++j) ~~^~~~~~~~~~~~~~~~~~~~