238. 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].

代码如下：

 public class Solution {
     public int[] productExceptSelf(int[] nums) {
         int[] output=new int[nums.length];
         List<Integer> list=new ArrayList<>();
         int sum=1;
         for(int i=0;i<nums.length;i++)
         {
             if(nums[i]!=0)
             sum=sum*nums[i];
             else list.add(i);
         }

         if(list.size()==1)
         {
             output[list.get(0)]=sum;
             return output;
         }
         else if(list.size()>1)
             return output;

         for(int i=0;i<nums.length;i++)
         output[i]=sum/nums[i];

         return output;

     }
 }