#include #define For(i, a, b) for(int (i)=(int)(a); (i)<(int)(b); ++(i)) #define rFor(i, a, b) for(int (i)=(int)(a)-1; (i)>=(int)(b); --(i)) #define rep(i, n) For((i), 0, (n)) #define rrep(i, n) rFor((i), (n), 0) #define fi first #define se second using namespace std; typedef long long lint; typedef unsigned long long ulint; typedef pair pii; typedef pair pll; template bool chmax(T &a, const T &b){if(a bool chmin(T &a, const T &b){if(a>b){a=b; return true;} return false;} template T div_floor(T a, T b){ if(b < 0) a *= -1, b *= -1; return a>=0 ? a/b : (a+1)/b-1; } template T div_ceil(T a, T b){ if(b < 0) a *= -1, b *= -1; return a>0 ? (a-1)/b+1 : a/b; } constexpr lint mod = 1e9+7; constexpr lint INF = mod * mod; constexpr int MAX = 200010; int main(){ int n, x; scanf("%d%d", &n, &x); int a[n]; rep(i, n) scanf("%d", &a[i]); map mp; rep(i, n) ++mp[a[i]]; lint ans = 0; for(auto p: mp){ lint q = x ^ p.fi; if(q < p.fi) continue; ans += (p.fi == q ? p.se*(p.se-1)/2 : p.se * mp[q]); } printf("%lld\n", ans); }