function triplets(a, b, c) {
  let cleanA = [...new Set(a)].sort((x, y) => x - y)
  let cleanB = [...new Set(b)]
  let cleanC = [...new Set(c)].sort((x, y) => x - y)
  let count = 0

  for (let i = 0; i < cleanB.length; i++) {
    let numOfP = 0, numOfQ = 0
    for (let j = cleanA.length; j > 0; j--) {
      if (cleanA[j - 1] <= cleanB[i]) {
        numOfP = j
        break
      }
    }
    for (let j = cleanC.length; j > 0; j--) {
      if (cleanC[j - 1] <= cleanB[i]) {
        numOfQ = j
        break
      }
    }
    count += numOfP * numOfQ
  }
  return count
}