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.
Example 1:
Input: nums = [1,2,3,4] Output: [24,12,8,6]
Example 2:
Input: nums = [-1,1,0,-3,3] Output: [0,0,9,0,0]
public int[] productExceptSelf(int[] nums) {
int[] prefix = new int[nums.length];
prefix[0]=1;
int[] suffix = new int[nums.length];
suffix[nums.length-1]=1;
for(int i=1;i<nums.length;i++){
prefix[i] = prefix[i-1]* nums[i-1];
suffix[nums.length-1-i] = suffix[nums.length-i] * nums[nums.length-i];
}
for(int i=0;i<nums.length;i++){
prefix[i] = prefix[i]*suffix[i];
}
return prefix;
}