Compilare: user.cpp: In function ‘int main()’: user.cpp:33:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < cat.size(); ++i) ^ user.cpp:34:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (z[i] >= pat.size()) ^ user.cpp: In function ‘void make_z(const string&, int*)’: user.cpp:21:28: warning: ‘l’ may be used uninitialized in this function [-Wmaybe-uninitialized] z[i] = min(z[i - l], r - i + 1); ^