Time – O(n)

Space – 0(1) – Neglecting the output array that is expected to be returned.

class Solution {
public int[] productExceptSelf(int[] nums) {
int n = nums.length;
int[] output = new int[n];
int temp = 1;
// product from left to right excluding nums[i]
for (int i = 0; i < n; i++) {
output[i] = temp;
temp *= nums[i];
}
temp = 1;
// product from right to left excluding nums[i]
for (int i = n - 1; i >= 0; i--) {
output[i] *= temp;
temp *= nums[i];
}
return output;
}
}

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