Product of Array Except Self
Detailed guide and Python implementation for the 'Product of Array Except Self' problem.
Problem Statement
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.
Write a function productExceptSelf(nums: List[int]) -> List[int].
- •2 <= len(nums) <= 10^5
- •-30 <= nums[i] <= 30
- •The product of any prefix or suffix of nums fits in a 32-bit integer
Examples
nums = [1, 2, 3, 4]
[24, 12, 8, 6]
answer[0] = 2*3*4 = 24, answer[1] = 1*3*4 = 12, answer[2] = 1*2*4 = 8, answer[3] = 1*2*3 = 6.
nums = [-1, 1, 0, -3, 3]
[0, 0, 9, 0, 0]
Any product that includes the 0 at index 2 becomes 0. answer[2] = (-1)*1*(-3)*3 = 9.
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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