#include <algorithm>
#include <bitset>
-#include <functional>
#ifdef _GLIBCXX_DEBUG
# include <iosfwd>
#endif
#include <cstring>
#include <ext/aligned_buffer.h>
+#include <bits/std_function.h>
#include <bits/regex_constants.h>
#include <bits/regex_error.h>
#include <bits/regex_automaton.h>