Compilare: user.cpp: In function ‘void build_prefix(std::string)’: user.cpp:39:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 2; i < p.size(); i++) ^ user.cpp: In function ‘void KMP()’: user.cpp:54:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < s.size(); i++) ^ user.cpp:61:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (k == pattern.size()-1) ^ user.cpp:52:7: warning: variable ‘ok’ set but not used [-Wunused-but-set-variable] bool ok; ^ user.cpp:70:1: warning: label ‘_end’ defined but not used [-Wunused-label] _end: ^