1726.js

/** ------------------------------------------------------------------------------
 * 
 * 1726. Tuple with Same Product
 * Topics: Array, Hash Table
 * https://leetcode.com/problems/tuple-with-same-product/?envType=daily-question&envId=2025-02-06
 * 
 ------------------------------------------------------------------------------ */
/**
 * @param {number[]} nums
 * @return {number}
 */
var tupleSameProduct = function (nums) {
  const n = nums.length
  const map = new Map()
  let count = 0

  for (let i = 0; i < n; i++) {
    const a = nums[i]

    for (let j = i + 1; j < n; j++) {
      const b = nums[j]

      const product = a * b
      const pairs = map.get(product) || 0

      count += pairs * 8

      map.set(product, pairs + 1)
    }
  }

  return count
}

var tupleSameProduct = function (nums) {
  const map = new Map()
  let count = 0
  let n = nums.length
  for (let i = 0; i < n; i++) {
    for (let j = i + 1; j < n; j++) {
      let product = nums[i] * nums[j]
      map.set(product, (map.get(product) || 0) + 1)
    }
  }

  for (let freq of map.values()) {
    if (freq > 1) {
      count += ((freq * (freq - 1)) / 2) * 8
    }
  }
  return count
}

console.log(tupleSameProduct([2, 3, 4, 6, 8, 12]))