<p>You are given an array <code>nums</code> of positive integers and a <strong>positive</strong> integer <code>k</code>.</p>

<p>A subset of <code>nums</code> is <strong>beautiful</strong> if it does not contain two integers with an absolute difference equal to <code>k</code>.</p>

<p>Return <em>the number of <strong>non-empty beautiful </strong>subsets of the array</em> <code>nums</code>.</p>

<p>A <strong>subset</strong> of <code>nums</code> is an array that can be obtained by deleting some (possibly none) elements from <code>nums</code>. Two subsets are different if and only if the chosen indices to delete are different.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> nums = [2,4,6], k = 2
<strong>Output:</strong> 4
<strong>Explanation:</strong> The beautiful subsets of the array nums are: [2], [4], [6], [2, 6].
It can be proved that there are only 4 beautiful subsets in the array [2,4,6].
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> nums = [1], k = 1
<strong>Output:</strong> 1
<strong>Explanation:</strong> The beautiful subset of the array nums is [1].
It can be proved that there is only 1 beautiful subset in the array [1].
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= nums.length &lt;= 20</code></li>
	<li><code>1 &lt;= nums[i], k &lt;= 1000</code></li>
</ul>

class Solution {
public:
    void helper(vector<int>& nums, vector<int> prev, int idx, int k, int& ans ){
        
        if(idx >= nums.size()){
            return;
        }
    //    1,2,4,5, 7, 10 
       
    //    2, 4, 7, 
    //    4
        for(int st = idx; st < nums.size(); st++){
            if(prev.size() != 0  ){
                int i =0; 
                for( i = 0; i< prev.size(); i++){
                    if( abs(nums[st] - prev[i]) == k)
                        break;
                    }
                if(i != prev.size()){
                    continue;
                }
            }
            prev.push_back(nums[st]);
            ans++;
            helper(nums, prev,st+1, k, ans);
            prev.pop_back();
          //  prev = -1;
        }
    }
    int beautifulSubsets(vector<int>& nums, int k) {
        //sort(nums.begin(), nums.end());
        int ans =0;
        vector<int> temp ;
        helper(nums, temp, 0, k, ans);
        return ans;
    }
};
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