Compilare: user.cpp: In function ‘int ZF(std::string, std::string)’: user.cpp:18:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < s.size(); i++) { ^ user.cpp:22:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int k = 0; k < s.size(); k++) { ^ user.cpp:27:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(right < s.size() && s[right] == s[right-left]) ^ user.cpp:39:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(right < s.size() && s[right] == s[right-left]) ^ user.cpp:47:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] am += (Z[k]==s1.size()); ^