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# Product of Array Except Self

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.)

```java
class Solution {
    // We cannot use division operator
    public int[] productExceptSelf(int[] nums) {
        int ans[] = new int[nums.length];
        int prev = 1;
        for (int i = 0; i < nums.length; i++) {
            ans[i] = prev;
            prev *= nums[i];
        }
        int next = 1;
        for (int i = nums.length - 1; i >= 0; i--) {
            ans[i] *= next;
            next *= nums[i];
        }
        return ans;
    }
}
```