Compilare: user.cpp: In function ‘void z_al(std::string, int*)’: user.cpp:15:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=1;i<s.size();i++) ^ user.cpp:21:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(r<s.size()&&s[r-l]==s[r]) r++; ^ user.cpp:34:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(r<s.size()&&s[r-k]==s[r]) r++; ^ user.cpp: In function ‘int main()’: user.cpp:55:30: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("x.in","r",stdin); ^ user.cpp:56:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("x.out","w",stdout); ^