Compilare: user.cpp: In function ‘int main()’: user.cpp:92:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i < a.size(); i++) ^ user.cpp:99:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i < b.size(); i++) ^ user.cpp:101:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(size < a.size()) ^ user.cpp:107:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(size == a.size()) ^ user.cpp:123:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < positions.size(); i++) ^