leetcode-152.js

var maxProduct = function(nums) {
  let max = -Infinity
  const memo = {}
  for (let i=0; i < nums.length; i++) {
    const result = dp(nums, i, nums.length, memo)
    if (result.max > max) {
        max = result.max
    }
  }
  return max
};

function dp(nums, start, end, memo) {
  if (end - start === 1) {
      return { min: nums[start], max: nums[start] }
  }

  if (memo[`${start}-${end}`]) {
    return memo[`${start}-${end}`]
  }

  const r = dp(nums, start + 1, end, memo)
  const max = Math.max(nums[start], nums[start] * r.max, nums[start] * r.min)
  const min = Math.min(nums[start], nums[start] * r.max, nums[start] * r.min)
  const result = { max , min }
  memo[`${start}-${end}`] = result
  return result
}