#include<bits/stdc++.h> using namespace std; #define ll long long const ll N=1e5+10,INF=-0x3f3f3f3f; ll n,k,a[N]; ll sum; ll ans; ll cur; signed main(){ ans=INF; scanf("%d%d",&n,&k); for(int i=1;i<=n;i++){ scanf("%d",&a[i]); sum+=a[i]; } for(int i=1;i<=n;i++){ cur=a[i]+(a[i]^k); ans=max(ans,cur); } ans+=sum; printf("%lld",ans); return 0; }