Compilare: user.cpp: In function ‘int main()’: user.cpp:71:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < a.size(); i++) ^ user.cpp:74:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < b.size(); i++) ^ user.cpp:76:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(size < a.size()) ^ user.cpp:82:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(size == a.size()) ^ user.cpp:98:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < positions.size(); i++) ^