<p>There is a room with <code>n</code> bulbs labeled from <code>1</code> to <code>n</code> that all are turned on initially, and <strong>four buttons</strong> on the wall. Each of the four buttons has a different functionality where:</p>

<ul>
	<li><strong>Button 1:</strong> Flips the status of all the bulbs.</li>
	<li><strong>Button 2:</strong> Flips the status of all the bulbs with even labels (i.e., <code>2, 4, ...</code>).</li>
	<li><strong>Button 3:</strong> Flips the status of all the bulbs with odd labels (i.e., <code>1, 3, ...</code>).</li>
	<li><strong>Button 4:</strong> Flips the status of all the bulbs with a label <code>j = 3k + 1</code> where <code>k = 0, 1, 2, ...</code> (i.e., <code>1, 4, 7, 10, ...</code>).</li>
</ul>

<p>You must make <strong>exactly</strong> <code>presses</code> button presses in total. For each press, you may pick <strong>any</strong> of the four buttons to press.</p>

<p>Given the two integers <code>n</code> and <code>presses</code>, return <em>the number of <strong>different possible statuses</strong> after performing all </em><code>presses</code><em> button presses</em>.</p>

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

<pre>
<strong>Input:</strong> n = 1, presses = 1
<strong>Output:</strong> 2
<strong>Explanation:</strong> Status can be:
- [off] by pressing button 1
- [on] by pressing button 2
</pre>

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

<pre>
<strong>Input:</strong> n = 2, presses = 1
<strong>Output:</strong> 3
<strong>Explanation:</strong> Status can be:
- [off, off] by pressing button 1
- [on, off] by pressing button 2
- [off, on] by pressing button 3
</pre>

<p><strong class="example">Example 3:</strong></p>

<pre>
<strong>Input:</strong> n = 3, presses = 1
<strong>Output:</strong> 4
<strong>Explanation:</strong> Status can be:
- [off, off, off] by pressing button 1
- [off, on, off] by pressing button 2
- [on, off, on] by pressing button 3
- [off, on, on] by pressing button 4
</pre>

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

<ul>
	<li><code>1 &lt;= n &lt;= 1000</code></li>
	<li><code>0 &lt;= presses &lt;= 1000</code></li>
</ul>

class Solution {
public:

    int count_bits(int x){
        int ans = 0;
        for(int i=0;i<4;i++){
            if((x&(1<<i)) != 0)ans++;
        }
        return(ans);
    }

    void my_xor(vector<int> &bulb, int id){
        for(int i=0;i<bulb.size();i++){
            if(id == 0)bulb[i] = abs(bulb[i]-1);
            if(id == 1 && i%2 == 0)bulb[i] = abs(bulb[i]-1);
            if(id == 2 && i%2 == 1)bulb[i] = abs(bulb[i]-1);
            if(id == 3 && i%3 == 0)bulb[i] = abs(bulb[i]-1);
        }
    }

    int flipLights(int n, int presses) {

        vector<int> bulb(n, 0);
        set<vector<int>> uni;


        for(int i=0;i<16;i++){
            if(count_bits(i) % 2 != presses % 2)continue;
            if(count_bits(i) > presses)continue;

            cout << i << endl;
            
            for(int k=0;k<n;k++)bulb[k] = 0;
            for(int j=0;j<4;j++){
                if((i&(1<<j)) == 0)continue;
                else my_xor(bulb, j);
            }
            uni.insert(bulb);
        }
        return(uni.size());
    }
};
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