#include using namespace std; using lint = long long; constexpr lint mod = 998244353; #define all(x) (x).begin(), (x).end() #define bitcount(n) __builtin_popcountl((lint)(n)) #define fcout cout << fixed << setprecision(15) #define highest(x) (63 - __builtin_clzl(x)) #define rep(i, n) for(int i = 0; i < int(n); i++) #define rep2(i, l, r) for(int i = int(l); i < int(r); i++) #define repr(i, n) for(int i = int(n) - 1; i >= 0; i--) #define repr2(i, l, r) for(int i = int(r) - 1; i >= int(l); i--) #define SZ(x) int(x.size()) constexpr int inf9 = 1e9; constexpr lint inf18 = 1e18; inline void YES(bool condition){ if(condition) cout << "YES" << endl; else cout << "NO" << endl; } inline void Yes(bool condition){ if(condition) cout << "Yes" << endl; else cout << "No" << endl; } inline void assert_NO(bool condition){ if(!condition){ cout << "NO" << endl; exit(0); } } inline void assert_No(bool condition){ if(!condition){ cout << "No" << endl; exit(0); } } inline void assert_m1(bool condition){ if(!condition){ cout << -1 << endl; exit(0); } } lint power(lint base, lint exponent, lint module){ if(exponent % 2){ return power(base, exponent - 1, module) * base % module; }else if(exponent){ lint root_ans = power(base, exponent / 2, module); return root_ans * root_ans % module; }else{ return 1; }} struct position{ int y, x; }; position mv[4] = {{0, -1}, {1, 0}, {0, 1}, {-1, 0}}; double euclidean(position first, position second){ return sqrt((second.x - first.x) * (second.x - first.x) + (second.y - first.y) * (second.y - first.y)); } template string to_string(pair x){ return to_string(x.first) + "," + to_string(x.second); } string to_string(string x){ return x; } template void array_output(itr start, itr goal){ string ans; for(auto i = start; i != goal; i++) ans += to_string(*i) + " "; if(!ans.empty()) ans.pop_back(); cout << ans << endl; } template void cins(itr first, itr last){ for(auto i = first; i != last; i++){ cin >> (*i); } } template T gcd(T a, T b){ if(b) return gcd(b, a % b); else return a; } template T lcm(T a, T b){ return a / gcd(a, b) * b; } struct combination{ vector fact, inv; combination(int sz) : fact(sz + 1), inv(sz + 1){ fact[0] = 1; for(int i = 1; i <= sz; i++){ fact[i] = fact[i - 1] * i % mod; } inv[sz] = power(fact[sz], mod - 2, mod); for(int i = sz - 1; i >= 0; i--){ inv[i] = inv[i + 1] * (i + 1) % mod; } } lint P(int n, int r){ if(r < 0 || n < r) return 0; return (fact[n] * inv[n - r] % mod); } lint C(int p, int q){ if(q < 0 || p < q) return 0; return (fact[p] * inv[q] % mod * inv[p - q] % mod); } }; template bool next_sequence(itr first, itr last, int max_bound){ itr now = last; while(now != first){ now--; (*now)++; if((*now) == max_bound){ (*now) = 0; }else{ return true; } } return false; } template bool next_sequence2(itr first, itr last, itr2 first2, itr2 last2){ itr now = last; itr2 now2 = last2; while(now != first){ now--, now2--; (*now)++; if((*now) == (*now2)){ (*now) = 0; }else{ return true; } } return false; } template bool chmax(T &a, const T &b){ if(a < b){ a = b; return 1; } return 0; } template bool chmin(T &a, const T &b){ if(b < a){ a = b; return 1; } return 0; } inline int at(lint i, int j){ return (i >> j) & 1; } random_device rnd; bool is_in_board(lint y, lint x, lint H, lint W){ return (0 <= y && y < H && 0 <= x && x < W); } int main(){ int N, X; cin >> N >> X; map cnt; lint ans = 0; rep(i, N){ lint A; cin >> A; ans += cnt[X ^ A]; cnt[A]++; } cout << ans << endl; }