local mfl, mce = math.floor, math.ceil
local function query(str)
  io.write(str .. "\n")
  io.flush()
  local ret = io.read("*l")
  return ret
end

local n, m = io.read("*n", "*n", "*l")
local t = {}
for i = 1, 4 * n * n do
  t[i] = false
end
local map = {}
-- 0:unknown, 1:black, 2:white
for i = 1, n * n do
  map[i] = 0
end
map[1], map[n * n] = 1, 1

local function checkmap(row, col)
  local mapidx = (row - 1) * n + col
  if map[mapidx] == 0 then
    local ans = query(row .. " " .. col)
    if ans == "Black" then
      map[mapidx] = 1
    else
      map[mapidx] = 2
    end
  end
end

local pos = 1
while true do
  -- print(pos)
  if t[pos] then
    io.write("No\n")
    io.flush()
    os.exit()
  end
  t[pos] = true
  local way = mce(pos / n / n)
  local mapidx = pos - (way - 1) * n * n
  if mapidx == n * n then
    io.write("Yes\n")
    io.flush()
    os.exit()
  end
  local row = mce(mapidx / n)
  local col = mapidx - (row - 1) * n
  if way == 1 then
    -- up
    if 1 < row then
      checkmap(row - 1, col)
    end
    if 1 < row and map[mapidx - n] == 1 then
      pos = 3 * n * n + (row - 2) * n + col
    else
      pos = 1 * n * n + (row - 1) * n + col
    end
  elseif way == 2 then
    -- right
    if col < n then
      checkmap(row, col + 1)
    end
    if col < n and map[mapidx + 1] == 1 then
      pos = 0 * n * n + (row - 1) * n + col + 1
    else
      pos = 2 * n * n + (row - 1) * n + col
    end
  elseif way == 3 then
    -- down
    if row < n then
      checkmap(row + 1, col)
    end
    if row < n and map[mapidx + n] == 1 then
      pos = 1 * n * n + row * n + col
    else
      pos = 3 * n * n + (row - 1) * n + col
    end
  else
    -- left
    if 1 < col then
      checkmap(row, col - 1)
    end
    if 1 < col and map[mapidx - 1] == 1 then
      pos = 2 * n * n + (row - 1) * n + col - 1
    else
      pos = 0 * n * n + (row - 1) * n + col
    end
  end
end