local bxor = bit.bxor
local mce, mfl, msq, mmi, mma, mab = math.ceil, math.floor, math.sqrt, math.min, math.max, math.abs
local lim = 1000 * 1000

local function getprimes(x)
  local primes = {}
  local allnums = {}
  for i = 1, x do allnums[i] = true end
  for i = 2, x do
    if allnums[i] then
      table.insert(primes, i)
      local lim = mfl(x / i)
      for j = 2, lim do
        allnums[j * i] = false
      end
    end
  end
  return primes
end
local tt = {}
for i = 1, lim do
  tt[i] = 0
end
local primes = getprimes(lim)
local pn = #primes
for i = 1, pn do
  local p = primes[i]
  local z = p
  while z <= lim do
    local y = z
    while y <= lim do
      tt[y] = tt[y] + 1
      y = y + z
    end
    z = z * p
  end
end

local n = io.read("*n", "*l")
local ret = 0
local s = io.read()
for w in s:gmatch("%d+") do
  local a = tonumber(w)
  ret = bxor(ret, tt[a])
end
print(ret == 0 and "black" or "white")