#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
#define REP(i,a,n) for(int i=(a); i<(int)(n); i++)
#define rep(i,n) REP(i,0,n)
#define FOR(it,c) for(__typeof((c).begin()) it=(c).begin(); it!=(c).end(); ++it)
#define ALLOF(c) (c).begin(), (c).end()
typedef long long ll;
typedef unsigned long long ull;
//using mint = modint1000000007;
//using mint = modint998244353;



int main(){
  int N;
  ll K;
  cin >> N >> K;
  vector<ll> v(N);
  rep(i,N) cin >> v[i];

  REP(i,N,(N+1)*N){
    ll x = 0;
    rep(j,N){
      x ^= v[i-1-j];
    }
    v.push_back(x);
  }

  cout << v[(K-1)%(v.size())] << endl;
  
  return 0;
}