Submission #3311114

---

Source Code Expand

n = gets.to_i
x = 0
bxor = Array.new(30,0)
ans = 0
n.times do
  a = gets.to_i
  x ^= a
  a ^= a-1
  30.downto(0) do |i|
    if a[i] == 1
      bxor[i] = 1
      break
    end
  end
end

29.downto(0) do |i|
  if x[i] == 1
    if bxor[i] == 1
      x ^= (1 << i+1)-1
      ans += 1
    else
      ans = -1
      break
    end
  end
end
p ans

Submission Info

Judge Result