#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll=long long;
using ld=long double;
ld pie=3.141592653589793;
ll inf=144494;
ll mod=1000000007;
int main(){
    ll n,k;
    cin >> n >> k;
    k--;
    vector<ll>a(n);
    ll x=0;
    for (ll i = 0; i < n; i++)
    {
        cin >> a[i];
        x^=a[i];
    }
    a.push_back(x);
    cout << a[k%(n+1)] << endl;
}