[LeetCode] 442. Find All Duplicates in an Array

题解来自 点击打开链接，

vector<int> findDuplicates(vector<int>& nums)
{
	vector<int> res;
	for(unsigned int i=0;i<nums.size();++i)
	{
		nums[abs(nums[i])-1]=-nums[abs(nums[i])-1];
		if(nums[abs(nums[i])-1]>0) res.push_back(abs(nums[i]));
	}
	return res;
}