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## Problem

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]


Constraint: It’s guaranteed that the product of the elements of any prefix or suffix of the array (including the whole array) fits in a 32 bit integer.

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.)

## Code

class Solution {
public int[] productExceptSelf(int[] nums) {
int[] res = new int[nums.length];

res = 1;

int curr = nums;
for(int i = 1; i < nums.length; i++) {
res[i] = curr;
curr *= nums[i];
}

curr = nums[nums.length - 1];
for(int i = nums.length - 2; i >= 0; i--){
res[i] *= curr;
curr *= nums[i];
}

return res;
}
}

class Solution:
def productExceptSelf(self, nums: List[int]) -> List[int]:
res = []

for i in range(len(nums)):
res.append(1)

curr = nums
for i in range(1, len(nums)):
res[i] = curr
curr *= nums[i]

curr = nums[-1]
for i in range(len(nums) - 2, -1, -1):
res[i] *= curr
curr *= nums[i]

return res