Compilare: user.cpp: In function ‘int main()’: user.cpp:16:74: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while( (ul = sir.find(subsir.c_str(), ul + 1, lungime)) != string :: npos) { ^ user.cpp:23:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < rez.size() and i < 1000; ++i) out << rez[i] << " "; ^