try.rb

n = gets.chomp.to_i

arr = []

n.times do
	temp =  gets.chomp.to_i
	arr.push temp
end

arr.sort!

arr.reverse!

sig = Math.log(arr[0], 2).to_i

t = 0

while sig >= 1

	i = t

	while i < n && (arr[i]&sig)==0
		i+=1
	end

	if i>=n
		next
	end

	arr[t],arr[i] = arr[i], arr[t]

	for j in 0..n-1

		if j!=t && (arr[j]&sig!=0)
			arr[j] = arr[j]^arr[t]
		end
	end

	t+=1

	sig>>=1

end

res = 0

for k in 0..n-1
	res = res^arr[k]
end

puts res