Compilare: user.cpp: In function ‘bool IsSmaller(std::vector<int>&, std::vector<int>&)’: user.cpp:68:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < a.size(); ++i) ^ user.cpp: In function ‘int main()’: user.cpp:87:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < a.size(); ++i) ^ user.cpp:88:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < a.size(); ++j) ^