Compilare: user.cpp: In function ‘int main()’: user.cpp:41:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int k = 0; k < R.size(); ++k, s += R[k]) ^ user.cpp:50:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int k = 0; k < A.size(); ++k, s += A[k]) ^