2044.js

/** ------------------------------------------------------------------------------
 * 
 * 2044. Count Number of Maximum Bitwise-OR Subsets
 * Topics: Backtrack, Bit
 * https://leetcode.com/problems/count-number-of-maximum-bitwise-or-subsets/?envType=daily-question&envId=2024-10-18
 * 
 ------------------------------------------------------------------------------ */
/**
 * @param {number[]} nums
 * @return {number}
 */
var countMaxOrSubsets = function (nums) {
  let result = 0,
    max = 0

  const backtrack = (num, start, val) => {
    if (val === max) result++

    for (let i = start; i < nums.length; i++) {
      backtrack(nums, i + 1, val | nums[i])
    }
  }

  for (let num of nums) max |= num
  backtrack(nums, 0, 0)
  return result
}

console.log()