Compilare: user.cpp: In function ‘int gen_hash(std::__cxx11::string)’: user.cpp:24:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<s.size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:51:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<pattern.size(); i++) ^ user.cpp:58:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<pattern.size() && !sem; i++) ^ user.cpp:83:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=i; j<i+pattern.size() && !sem; j++) ^ user.cpp:104:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<res.size(); i++) ^