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].

代码如下：

 1 public class Solution {
 2     public int[] productExceptSelf(int[] nums) {
 3         int[] output=new int[nums.length];
 4         List<Integer> list=new ArrayList<>();
 5         int sum=1;
 6         for(int i=0;i<nums.length;i++)
 7         {
 8             if(nums[i]!=0)
 9             sum=sum*nums[i];
10             else list.add(i);
11         }
12         
13         if(list.size()==1)
14         {
15             output[list.get(0)]=sum;
16             return output;
17         }
18         else if(list.size()>1)
19             return output;
20             
21         for(int i=0;i<nums.length;i++)
22         output[i]=sum/nums[i];
23         
24         return output;
25         
26         
27     }
28 }