#define _USE_MATH_DEFINES #include using namespace std; //template #define rep(i,a,b) for(int i=(int)(a);i<(int)(b);i++) #define ALL(v) (v).begin(),(v).end() typedef long long int ll; const int inf = 0x3fffffff; const ll INF = 0x1fffffffffffffff; const double eps=1e-12; templateinline bool chmax(T& a,T b){if(ainline bool chmin(T& a,T b){if(a>b){a=b;return 1;}return 0;} //end int main(){ int n,x; cin>>n>>x; ll res=0; map cnt; rep(i,0,n){ int a; cin>>a; res+=cnt[a^x]; cnt[a]++; } cout<