def f(A,K):
    B=A.copy()
    while len(B)<K:
        x=0
        for a in A:
            x^=a
        del A[0]
        A.append(x)
        B.append(x)
    return B

N,K=map(int,input().split())
A=list(map(int,input().split()))

x=0
for a in A: x^=a
A.append(x)

K-=1
print(A[K%(N+1)])