Given an array nums
of n integers where n > 1, return an array output
such that output[i]
is equal to the product of all the elements of nums
except nums[i]
.
Example:
Input:[1,2,3,4]
Output:[24,12,8,6]
Note: Please solve it without division and in O(n).
Follow up:
Could you solve it with constant space complexity? (The output array does not count as extra space for the purpose of space complexity analysis.)
class Solution { public int[] productExceptSelf(int[] nums) { if (nums == null || nums.length == 0) { return nums; } int[] resArr = new int[nums.length]; resArr[0] = 1; for (int i = 1; i < nums.length; i++) { resArr[i] = resArr[i - 1] * nums[i - 1]; } int right = 1; for (int i = nums.length - 1; i >= 0; i--) { resArr[i] *= right; right *= nums[i]; } return resArr; } }