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@fever324
Created August 31, 2015 23:44
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Product of Array Except Self
/*
Given an array of n integers where n > 1, nums, return an array output such that output[i] is equal to the product of all the elements of nums except nums[i].
Solve it without division and in O(n).
For example, given [1,2,3,4], return [24,12,8,6].
Follow up:
Could you solve it with constant space complexity? (Note: The output array does not count as extra space for the purpose of space complexity analysis.)
*/
public class Solution {
public int[] productExceptSelf(int[] nums) {
int[] result = new int[nums.length];
result[0] = 1;
for(int i = 1; i < nums.length; i++) {
result[i] = nums[i-1] * result[i-1];
}
int right = 1;
for(int i = nums.length -1; i >= 0; i--) {
result[i] = right * result[i];
right *= nums[i];
}
return result;
}
}
@gilles-yvetot
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but this is O(2n) ?

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