Compilare: main.cpp: In member function 'void manacher::solve()': main.cpp:44:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=1;i<s.size();i++){ ~^~~~~~~~~ main.cpp:49:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (i - lg >= 0 && i + lg < s.size() && s[i - lg] == s[i + lg]) lg++; ~~~~~~~^~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:81:33: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("pscpld.in","r",stdin); ^ main.cpp:82:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("pscpld.out","w",stdout); ^