Compilare: user.cpp: In function ‘int* precalc(const string&)’: user.cpp:12:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=1;i<pat.size();i++) ^ user.cpp: In function ‘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,j=0;i<txt.size();) ^ user.cpp:37:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(j==pat.size()) ^