<p>In a warehouse, there is a row of barcodes, where the <code>i<sup>th</sup></code> barcode is <code>barcodes[i]</code>.</p>

<p>Rearrange the barcodes so that no two adjacent barcodes are equal. You may return any answer, and it is guaranteed an answer exists.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<pre><strong>Input:</strong> barcodes = [1,1,1,2,2,2]
<strong>Output:</strong> [2,1,2,1,2,1]
</pre><p><strong class="example">Example 2:</strong></p>
<pre><strong>Input:</strong> barcodes = [1,1,1,1,2,2,3,3]
<strong>Output:</strong> [1,3,1,3,1,2,1,2]
</pre>
<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= barcodes.length &lt;= 10000</code></li>
	<li><code>1 &lt;= barcodes[i] &lt;= 10000</code></li>
</ul>

class Solution {
public:
    vector<int> rearrangeBarcodes(vector<int>& barcodes) {
        int n=barcodes.size();
        priority_queue<pair<int,int>> pq;
        int maxi=0;
        
        for(int i=0;i<n;i++){
            maxi=max(barcodes[i],maxi);
        }
        vector<int> count(maxi+1,0);
        for(int i=0;i<n;i++){
            count[barcodes[i]]++;
        }
        for(int i=0;i<count.size();i++){
            if(count[i]!=0){
                pq.push({count[i],i});
            }
        }
        int index=0;
        vector<int> ans(n);
        while(!pq.empty()){
            auto parent1=pq.top();
            //pq.pop();
            int x1=parent1.first;
            int y1=parent1.second;
            ans[index]=y1;
            index++;
            
            int x2=-1;
            int y2=-1;
            pq.pop();
            if(!pq.empty()){
                auto parent2=pq.top();
                pq.pop();
                x2=parent2.first;
                y2=parent2.second;
                ans[index]=y2;
                index++;
                if(x2-1>0){
                    pq.push({x2-1,y2});
                }
            }
            if(x1-1>0){
                pq.push({x1-1,y1});
            }
            
        }
        return ans;
    }
};
42000