#include<bits/stdc++.h>
using namespace std;
using ll = long long;

int main(){
  ll n,b;
  cin >> n >> b;
  vector<ll> a(n);
  for(int i = 0; i < n; i++){
    cin >> a[i];
  }
  sort(a.begin(),a.end());
  int ans = 0;
  for(int i = 0; i < n; i++){
    if(b >= a[i]){
      b ^= a[i];
      ans++;
    }
    else{
      break;
    }
  }
  cout << ans << endl;
}