class SegmentTree
	def initialize(v)
		@n = 1
		while @n < v.length do
			@n *= 2
		end
		@node = Array.new(2*@n-1, 0)
		v.each_with_index{|x, i|
			@node[i+@n-1] = x
		}
		(@n-2).downto(0) {|i|
			@node[i] = @node[2*i+1] ^ @node[2*i+2]
		}
	end
	def query(a, b, k=0, l=0, r=@n)
		if r <= a or b <= l then
			return 0
		end
		if a <= l and r <= b then
			return @node[k]
		else
			vl = query(a, b, k * 2 + 1, l, (l + r) / 2)
			vr = query(a, b, k * 2 + 2, (l + r) / 2, r)
			return vl ^ vr
		end
	end
end

N, Q = gets.split(" ").map{|s| s.to_i}
a = gets.split(" ").map{|s| s.to_i}

q = []
Q.times {
	q << gets.split(" ").map(&:to_i)
}

st = SegmentTree.new(a)

q.each {|l, r|
	puts st.query(l-1, r)
}