#include <stdio.h>
#include <bits/stdc++.h>
#include <atcoder/all>
using namespace atcoder;
using mint = modint998244353;
using namespace std;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define Inf 1000000001

int main(){
	
	int N;
	long long K;
	cin>>N>>K;
	
	vector<long long> A(N);
	long long t = 0LL;
	rep(i,N){
		cin>>A[i];
		t ^= A[i];
	}
	
	A.push_back(t);
	
	K--;
	K %= A.size();
	
	cout<<A[K]<<endl;
	
    return 0;
}