Problem:
Score : 300 points

Problem Statement

The season for Snuke Festival has come again this year. First of all, Ringo will perform a ritual to summon Snuke. For the ritual, he needs an altar, which consists of three parts, one in each of the three categories: upper, middle and lower.

He has N parts for each of the three categories. The size of the i-th upper part is A_i, the size of the i-th middle part is B_i, and the size of the i-th lower part is C_i.

To build an altar, the size of the middle part must be strictly greater than that of the upper part, and the size of the lower part must be strictly greater than that of the middle part. On the other hand, any three parts that satisfy these conditions can be combined to form an altar.

How many different altars can Ringo build? Here, two altars are considered different when at least one of the three parts used is different.

Constraints

1 \leq N \leq 10^5

1 \leq A_i \leq 10^9(1\leq i\leq N)

1 \leq B_i \leq 10^9(1\leq i\leq N)

1 \leq C_i \leq 10^9(1\leq i\leq N)

All input values are integers.

Input

Input is given from Standard Input in the following format:

N
A_1 ... A_N
B_1 ... B_N
C_1 ... C_N

Output

Print the number of different altars that Ringo can build.

Sample Input 1

2
1 5
2 4
3 6

Sample Output 1

3

The following three altars can be built:

Upper: 1-st part, Middle: 1-st part, Lower: 1-st part

Upper: 1-st part, Middle: 1-st part, Lower: 2-nd part

Upper: 1-st part, Middle: 2-nd part, Lower: 2-nd part

Sample Input 2

3
1 1 1
2 2 2
3 3 3

Sample Output 2

27

Sample Input 3

6
3 14 159 2 6 53
58 9 79 323 84 6
2643 383 2 79 50 288

Sample Output 3

87

Solution in Scala (2.13.1) (judge verdict: Accepted)

import java.io.{BufferedOutputStream, BufferedReader, InputStreamReader, PrintWriter}
import java.lang

import scala.annotation.tailrec
import scala.collection.mutable.ArrayBuffer
import scala.reflect.ClassTag

object Main {
  val DEBUG = false

  def log(message: => String): Unit = {
    if (DEBUG) {
      Console.err.println(message)
    }
  }

  def debug(closure: => Unit): Unit = {
    if (DEBUG) {
      closure
    }
  }

  def get[T: ClassTag](implicit in: BufferedReader, converter: String => T): T = {
    converter(in.readLine)
  }

  def getArray[T: ClassTag](implicit in: BufferedReader, converter: String => T): Array[T] = {
    get[String].split("\\s+").map[T](converter)
  }

  implicit val idConverter: String => String = s => s
  implicit val intConverter: String => Int = s => Integer.parseInt(s)
  implicit val longConverter: String => Long = s => lang.Long.parseLong(s)

  def get[T1, T2](
                   implicit in: BufferedReader,
                   converter1: String => T1,
                   converter2: String => T2
                 ): (T1, T2) = {
    getArray[String] match {
      case Array(v1, v2) => (converter1(v1), converter2(v2))
    }
  }

  def get[T1, T2, T3](
                       implicit in: BufferedReader,
                       converter1: String => T1,
                       converter2: String => T2,
                       converter3: String => T3
                     ): (T1, T2, T3) = {
    getArray[String] match {
      case Array(v1, v2, v3) => (converter1(v1), converter2(v2), converter3(v3))
    }
  }

  def get[T1, T2, T3, T4](
                           implicit in: BufferedReader,
                           converter1: String => T1,
                           converter2: String => T2,
                           converter3: String => T3,
                           converter4: String => T4
                         ): (T1, T2, T3, T4) = {
    getArray[String] match {
      case Array(v1, v2, v3, v4) => (converter1(v1), converter2(v2), converter3(v3), converter4(v4))
    }
  }

  implicit class TimesInt(val n: Int) {
    def times(f: Int => Unit): Unit = {
      for (i <- 0 until n) {
        f(i)
      }
    }
  }

  def primes(n: Long): ArrayBuffer[Long] = {
    val buf = ArrayBuffer.empty[Long]
    val s = Math.sqrt(n).toInt

    var v = n
    for (i <- 2 to s) {
      if (v == 1 || v == 0) {
        return buf
      } else {
        while (v % i == 0) {
          buf.append(i)
          v /= i
        }
      }
    }
    if (v > s) {
      buf.append(v)
    }
    buf
  }

  def divisors(n: Int): ArrayBuffer[Int] = {
    val buf = ArrayBuffer.empty[Int]
    val s = Math.sqrt(n).toInt

    for (i <- 1 to s) {
      if (n % i == 0) {
        buf.append(i)
        if (i != n / i) {
          buf.append(n / i)
        }
      }
    }
    buf
  }

  @tailrec
  def gcd(a: Long, b: Long): Long = {
    val reminder = a % b
    if (reminder == 0) {
      b
    } else {
      gcd(b, reminder)
    }
  }

  @tailrec
  def gcd(a: Int, b: Int): Int = {
    val reminder = a % b
    if (reminder == 0) {
      b
    } else {
      gcd(b, reminder)
    }
  }

  def lcm(a: Long, b: Long): Long = {
    a / gcd(a, b) * b
  }

  def toBitArray(n: Int, width: Int): Array[Boolean] = {
    val buf = ArrayBuffer.fill(width)(false)

    @tailrec
    def inner(n: Int, i: Int): Array[Boolean] = {
      buf(i) = (n & 1) == 0
      if (i == 0) {
        buf.toArray
      } else {
        inner(n / 2, i - 1)
      }
    }

    inner(n, width - 1)
  }

  def modpow(n: Long, p: Long, m: Long): Long = {
    @tailrec
    def inner(n: Long, p: Long, acc: Long): Long = {
      if (p == 0) {
        acc
      } else if ((p & 1) == 0) {
        inner(n * n % m, p >> 1, acc)
      } else {
        inner(n * n % m, p >> 1, acc * n % m)
      }
    }

    inner(n % m, p, 1)
  }

  def main(args: Array[String]): Unit = {
    implicit val in: BufferedReader = new BufferedReader(new InputStreamReader(System.in))
    val out = new PrintWriter(new BufferedOutputStream(System.out))
    val n = get[Int]
    val as = getArray[Int].sorted
    val bs = getArray[Int].sorted
    val cs = getArray[Int].sorted

    val csum = Array.ofDim[Long](n)
    val bsum = Array.ofDim[Long](n)
    val asum = Array.ofDim[Long](n)

    for (i <- n - 1 to 0 by -1) {
      csum(i) = n - i
    }

    def findFirstBiggerIndex(x: Int, ys: Array[Int], upperBoundIndex: Int): Int = {
      @tailrec
      def binarySearch(l: Int, r: Int): Int = {
        if (l + 1 == r) {
          l + 1
        } else {
          val m = (l + r) / 2
          if (x < ys(m)) {
            binarySearch(l, m)
          } else {
            binarySearch(m, r)
          }
        }
      }

      binarySearch(-1, upperBoundIndex)
    }

    var upperBoundIndex = n
    for (i <- n - 1 to 0 by -1) {
      val index = findFirstBiggerIndex(bs(i), cs, upperBoundIndex)
      if (index != n) {
        bsum(i) = csum(index)
      }
      if (i != n - 1) {
        bsum(i) += bsum(i + 1)
      }
      upperBoundIndex = index
    }

    upperBoundIndex = n
    for (i <- n - 1 to 0 by -1) {
      val index = findFirstBiggerIndex(as(i), bs, upperBoundIndex)
      if (index != n) {
        asum(i) = bsum(index)
      }
      if (i != n - 1) {
        asum(i) += asum(i + 1)
      }
      upperBoundIndex = index
    }

    out.println(asum.head)

    out.flush()
  }
}