求问

namespace Space{

	inline auto
	getc() -> char {
		constexpr int SIZE = 1 << 14;
		static char buf[SIZE], *begin = buf, *end = buf;
		if (begin == end) {
			begin = buf;
			end = buf + fread(buf, 1, SIZE, stdin);
		} return *begin ++;
	}

	template < typename _Tp > inline auto
	read(_Tp& t) -> void {
		int f = 0, ch = getc (); t = 0;
		while (!isdigit(ch)) f |= ch == '-', ch = getc ();
		do {t = (t << 1) + (t << 3) + (ch ^ '0'); ch = getc ();}
		while (isdigit(ch)); t = f ? -t : t;
	}

	template < typename _Tp, typename... _Args > inline auto
	read(_Tp& t, _Args&... args) -> void {
		read(t);read(args...);
	} 
} using namespace Space;