Compilare: main.cpp: In function 'void precompute(std::__cxx11::string)': main.cpp:26:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(j < s.size()) { ~~^~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:48:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = s1.size(); i < s1.size() + s2.size() + 1; i++) { ~~^~~~~~~~~~~~~~~~~~~~~~~~~~~ main.cpp:49:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(pref[i] == s1.size()) { ~~~~~~~~^~~~~~~~~~~~ main.cpp:60:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < res.size(); i++) ~~^~~~~~~~~~~~