<p>Alice has some number of cards and she wants to rearrange the cards into groups so that each group is of size <code>groupSize</code>, and consists of <code>groupSize</code> consecutive cards.</p>

<p>Given an integer array <code>hand</code> where <code>hand[i]</code> is the value written on the <code>i<sup>th</sup></code> card and an integer <code>groupSize</code>, return <code>true</code> if she can rearrange the cards, or <code>false</code> otherwise.</p>

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

<pre>
<strong>Input:</strong> hand = [1,2,3,6,2,3,4,7,8], groupSize = 3
<strong>Output:</strong> true
<strong>Explanation:</strong> Alice&#39;s hand can be rearranged as [1,2,3],[2,3,4],[6,7,8]
</pre>

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

<pre>
<strong>Input:</strong> hand = [1,2,3,4,5], groupSize = 4
<strong>Output:</strong> false
<strong>Explanation:</strong> Alice&#39;s hand can not be rearranged into groups of 4.

</pre>

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

<ul>
	<li><code>1 &lt;= hand.length &lt;= 10<sup>4</sup></code></li>
	<li><code>0 &lt;= hand[i] &lt;= 10<sup>9</sup></code></li>
	<li><code>1 &lt;= groupSize &lt;= hand.length</code></li>
</ul>

<p>&nbsp;</p>
<p><strong>Note:</strong> This question is the same as 1296: <a href="https://leetcode.com/problems/divide-array-in-sets-of-k-consecutive-numbers/" target="_blank">https://leetcode.com/problems/divide-array-in-sets-of-k-consecutive-numbers/</a></p>

class Solution {
public:
    bool isNStraightHand(vector<int>& a, int k) {
        sort(a.begin(), a.end());
        int n = a.size();
        if(n%k != 0) return false;

        priority_queue<pair<int, int>> pq;
        int i=0;
        while(i<n){
            int x = a[i];
            int cnt=1; i++;
            while(i<n && a[i]==a[i-1]) {cnt++; i++;}
            pair<int, int> p;
            p.first = x; p.second = cnt;
            pq.push(p);
        }

        while(!pq.empty()){
            int x = k;
            vector<pair<int,int>> st;
            while(!pq.empty() && x>0){
                x--;
                int y = pq.top().first;
                cout<<y<<endl;
                if(pq.top().second > 1) {
                    pair<int, int> p;
                    p.first = y; p.second = pq.top().second-1;
                    st.push_back(p);
                }
                pq.pop();
                if(x>0 && pq.top().first!=y-1) return false;
            }
            if(x>0) return false;
            for( auto j : st){
                pq.push(j);
            }
        }

        return true;
    }
};
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