object Main extends App {
  val Array(n, k) = io.StdIn.readLine().split(' ').map(_.toInt)
  val k2 = k * 2
  var (sum, white) = (0, 0)
  val matrix = new Array[Array[Int]](k2)
  (0 to k2-1).foreach(i => matrix(i) = new Array[Int](k2))
  def inc(x: Int, y: Int, z: Int) = {
    for {
      i <- (x to k2-1)
      j <- (y to k2-1)
    } {
      matrix(i)(j) = matrix(i)(j) + z
    }
  }
  (0 to n-1).foreach { i =>
    val temp = io.StdIn.readLine().split(' ')
      if (temp(2) == "B") {
        sum = sum + 1
        matrix(temp(0).toInt % k2)(temp(1).toInt % k2) = 1
      }
      else {
        sum = sum - 1
        white = white + 1
        matrix(temp(0).toInt % k2)(temp(1).toInt % k2) = -1
      }
  }
  for {
    i <- (1 to k2-1)
    j <- (1 to k2-1)
  } matrix(i)(j) = matrix(i)(j) + matrix(i-1)(j)
  for {
    i <- (1 to k2-1)
    j <- (1 to k2-1)
  } matrix(i)(j) = matrix(i)(j) + matrix(i)(j-1)
  val cnt =
      (matrix(k-1)(k-1)) +
      (matrix(k2-1)(k2-1) - matrix(k-1)(k2-1) - matrix(k2-1)(k-1) + matrix(k-1)(k-1))
  var max = Math.max(cnt, sum - cnt)
  for { 
    i <- (0 to k-1)
    j <- (0 to k-1)
  } {
    val cnt = 
      (matrix(i)(j)) +
      (matrix(i+k)(j+k) - matrix(i+k)(j) - matrix(i)(j+k) + matrix(i)(j)) +
      (matrix(k2-1)(j) - matrix(i+k)(j)) +
      (matrix(i)(k2-1) - matrix(i)(j+k)) +
      (matrix(k2-1)(k2-1) - matrix(k2-1)(j+k) - matrix(i+k)(k2-1) + matrix(i+k)(j+k))
    max = Math.max(Math.max(cnt, sum - cnt), max)
  }
  print(max + white)
}
