N,Q = map(int, input().split())
A = [int(a) for a in input().split()]

L = [0]*(N+1)
for i in range(N):
    L[i+1] = L[i]^A[i]

for _ in range(Q):
    l,r = map(int, input().split())
    print(L[r]^L[l-1])