Compilare: main.cpp: In function 'void Huffman(std::vector<std::pair<long long int, long long int> >)': main.cpp:84:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < h.size(); i++) { ~~^~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:155:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(s.size() < maxim) { ~~~~~~~~~^~~~~~~