There are some beautiful girls in Arpa’s land as mentioned before.

Once Arpa came up with an obvious problem:

Given an array and a number x, count the number of pairs of indices i, j (1 ≤ i < j ≤ n) such that <image>, where <image> is bitwise xor operation (see notes for explanation).

<image>

Immediately, Mehrdad discovered a terrible solution that nobody trusted. Now Arpa needs your help to implement the solution to that problem.

Input

First line contains two integers n and x (1 ≤ n ≤ 105, 0 ≤ x ≤ 105) — the number of elements in the array and the integer x.

Second line contains n integers a1, a2, ..., an (1 ≤ ai ≤ 105) — the elements of the array.

Output

Print a single integer: the answer to the problem.

Examples

Input

2 3
1 2


Output

1

Input

6 1
5 1 2 3 4 1


Output

2

Note

In the first sample there is only one pair of i = 1 and j = 2. <image> so the answer is 1.

In the second sample the only two pairs are i = 3, j = 4 (since <image>) and i = 1, j = 5 (since <image>).

A bitwise xor takes two bit integers of equal length and performs the logical xor operation on each pair of corresponding bits. The result in each position is 1 if only the first bit is 1 or only the second bit is 1, but will be 0 if both are 0 or both are 1. You can read more about bitwise xor operation here: <https://en.wikipedia.org/wiki/Bitwise_operation#XOR>.
#include <bits/stdc++.h>
using namespace std;
template <typename T>
T trace2(T a, T b) {
  cerr << a << " " << b << '\n';
}
template <typename T>
T trace3(T a, T b, T c) {
  cerr << a << " " << b << " " << c << '\n';
}
template <typename T>
T trace4(T a, T b, T c, T d) {
  cerr << a << " " << b << " " << c << " " << d << '\n';
}
template <typename T>
T trace5(T a, T b, T c, T d, T e) {
  cerr << a << " " << b << " " << c << " " << d << " " << e << '\n';
}
template <typename T>
T trace6(T a, T b, T c, T d, T e, T f) {
  cerr << a << " " << b << " " << c << " " << d << " " << e << " " << f << '\n';
}
void err(istream_iterator<string> it) {}
template <typename T, typename... Args>
void err(istream_iterator<string> it, T a, Args... args) {
  cerr << *it << " = " << a << '\n';
  err(++it, args...);
}
template <typename T>
T pow(T a, T b, long long int m) {
  T ans = 1;
  while (b > 0) {
    if (b % 2 == 1) ans = (ans * a) % m;
    b /= 2;
    a = (a * a) % m;
  }
  return ans % m;
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(NULL);
  cout.tie(NULL);
  ;
  long long int n, x;
  cin >> n >> x;
  std::vector<int> arr;
  std::map<int, int> map;
  for (__typeof(n) i = (0) - ((0) > (n)); i != (n) - ((0) > (n));
       i += 1 - 2 * ((0) > (n))) {
    int temp;
    cin >> temp;
    arr.push_back(temp);
    map[arr[i]]++;
  }
  long long int ans = 0;
  for (__typeof(n) i = (0) - ((0) > (n)); i != (n) - ((0) > (n));
       i += 1 - 2 * ((0) > (n))) {
    int temp = arr[i];
    temp = temp ^ x;
    ans += map[temp];
    if (temp == arr[i]) ans--;
  }
  ans = ans / 2;
  cout << ans << '\n';
  return 0;
}
