object Main extends App {
  val sc = new FastScanner(System.in)
  val n, k = sc.nextInt()
  val xyc = List.fill(n)((sc.nextInt(), sc.nextInt(), sc.next() == "B"))

  def compose(x1: Int, x2: Int): Int = {
    x1 * (k+1) + x2
  }

  var b = Array.fill((k+1) * (k+1))(0)
  var w = Array.fill((k+1) * (k+1))(0)

  for ((x, y, c) <- xyc) {
    val qx = x / k
    val qy = y / k
    if (c ^ ((qx + qy) % 2 == 1)) {
      b(compose(x % k + 1, y % k + 1)) += 1
    } else {
      w(compose(x % k + 1, y % k + 1)) += 1
    }
  }

  for {
    i <- 1 to k
    j <- 1 to k
  } {
    b(compose(i, j)) += b(compose(i, j-1))
    w(compose(i, j)) += w(compose(i, j-1))
  }

  for {
    j <- 1 to k
    i <- 1 to k
  } {
    b(compose(i, j)) += b(compose(i-1, j))
    w(compose(i, j)) += w(compose(i-1, j))
  }

  var ans = 0
  for {
    i <- 0 to k
    j <- 0 to k
  } {
    val wc = w(compose(k, k)) - w(compose(i, k)) - w(compose(k, j)) + 2 * w(compose(i, j))
    val bc = b(compose(i, k)) + b(compose(k, j)) - 2 * b(compose(i, j))
    ans = ans.max(wc + bc)
  }
  println(ans)
}

class FastScanner(source: java.io.InputStream) {
  val buf = new Array[Byte](1024)
  var now, end = 0

  def isPrintable(b: Byte): Boolean = 33 <= b && b <= 126
  def isNum(b: Byte): Boolean = 48 <= b && b <= 57

  def hasNextByte: Boolean = {
    if (now < end) {
      true
    } else {
      now = 0
      end = source.read(buf)
      end > 0
    }
  }

  def nextByte(): Byte = {
    if (hasNextByte) {
      val b = buf(now)
      now += 1
      b
    } else {
      -1
    }
  }

  def hasNext: Boolean = {
    while (hasNextByte && !isPrintable(buf(now))) {
      now += 1
    }
    hasNextByte
  }

  def next(): String = {
    if (hasNext) {
      val sb = new StringBuilder()
      var b = nextByte()
      while (isPrintable(b)) {
        sb += b.toChar
        b = nextByte()
      }
      sb.toString
    } else {
      throw new NoSuchElementException()
    }
  }

  def nextInt(): Int = {
    nextLong().toInt
  }

  def nextLong(): Long = {
    if (hasNext) {
      var b = nextByte()
      var sign = 1
      var n = 0L
      if (b == '-') {
        sign = -1
        b = nextByte()
      }
      while (isNum(b)) {
        n = n * 10 + (b - 48)
        b = nextByte()
      }
      sign * n
    } else {
      throw new NoSuchElementException()
    }
  }

  def nextDouble(): Double = next().toDouble
}
