Compilare: main.cpp: In function 'int main()': main.cpp:44:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = A.size() + 1; i < z.size(); ++i) ~~^~~~~~~~~~ main.cpp:45:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (z[i] == A.size())