Compilare: user.cpp: In function ‘std::vector<int> FindPrefixes(const string&)’: user.cpp:13:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i < s.size(); ++i) { ^ user.cpp: In function ‘std::pair<int, std::vector<int> > KMP(const string&, const string&)’: user.cpp:30:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < t.size(); ++i) { ^ user.cpp:35:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (k == w.size()) { ^