Given an integer array nums, return an array answer such that answer[i] is equal to the product of all the elements of nums except nums[i].
The product of any prefix or suffix of nums is guaranteed to fit in a 32-bit integer.
You must write an algorithm that runs in O(n) time and without using the division operation.
Example 1:
Input: nums = [1,2,3,4]
Output: [24,12,8,6]
Example 2:
Input: nums = [-1,1,0,-3,3]
Output: [0,0,9,0,0]
Solution
class Solution:
def productExceptSelf(self, nums: List[int]) -> List[int]:
l = [1] * (len(nums))
prefix, postfix = 1, 1
for i in range(len(nums)):
l[i] = prefix
prefix *= nums[i]
for j in range(len(nums) - 1, -1, -1):
l[j] *= postfix
postfix *= nums[j]
return l