func main()
	var n: int :: cui@inputInt()
	var x: bit64 :: cui@inputInt() $ bit64
	var a: []bit64 :: #[n]bit64
	var dic: dict<bit64, int> :: #dict<bit64, int>
	for i(0, n - 1)
		do a[i] :: cui@inputInt() $ bit64
		var xor: bit64 :: a[i].xor(x)
		do dic.add(xor, dic.get(xor, &) + 1)
	end for
	var ans: int :: 0
	for i(0, n - 1)
		do ans :+ dic.get(a[i], &)
	end for
	do ans :/ 2
	if(x = 0b64)
		do ans :- n
	end if
	do cui@print("\{ans}\n")
end func