4.js

/** ------------------------------------------------------------------------------
 * 
 * 4. Median of Two Sorted Arrays
 * Topics: Array
 * https://leetcode.com/problems/median-of-two-sorted-arrays/description/
 * 
 ------------------------------------------------------------------------------ */
/**
 * @param {number[]} nums1
 * @param {number[]} nums2
 * @return {number}
 */
// var findMedianSortedArrays = function (nums1, nums2) {
//   const array = [...nums1, nums2].sort((a, b) => a - b)
//   console.log(array.length)
//   const half = array[(array.length - 1) / 2]
//   console.log(half)

//   if (array.length % 2 === 0) {
//     return (half + array[array.lenth / 2]) / 2
//   }

//   return half
// }

var findMedianSortedArrays = function (nums1, nums2) {
  let len1 = nums1.length
  let len2 = nums2.length

  let total = len1 + len2
  let midIndex = Math.floor(total / 2)

  let i = 0,
    j = 0,
    count = 0
  let current = 0,
    prev = 0

  while (count <= midIndex) {
    prev = current

    if (i < len1 && (j >= len2 || nums1[i] <= nums2[j])) {
      current = nums1[i]
      i++
    } else {
      current = nums2[j]
      j++
    }

    count++
  }
  return total % 2 === 1 ? current : (current + prev) / 2
}

console.log()