Compilare: main.cpp: In function 'void aduna(std::vector<int>&, std::vector<int>)': main.cpp:13:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < a.size(); ++i) { ~~^~~~~~~~~~ main.cpp:14:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (i < b.size()) ~~^~~~~~~~~~ main.cpp:17:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (i + 1 >= a.size()) ~~~~~~^~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:54:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (i < pd[!turn][1].size() - 1) { ~~^~~~~~~~~~~~~~~~~~~~~~~~~