<p>Given an array of integers&nbsp;<code>arr</code>&nbsp;and an integer <code>k</code>.&nbsp;Find the <em>least number of unique integers</em>&nbsp;after removing <strong>exactly</strong> <code>k</code> elements<b>.</b></p>

<ol>
</ol>

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

<pre>
<strong>Input: </strong>arr = [5,5,4], k = 1
<strong>Output: </strong>1
<strong>Explanation</strong>: Remove the single 4, only 5 is left.
</pre>
<strong class="example">Example 2:</strong>

<pre>
<strong>Input: </strong>arr = [4,3,1,1,3,3,2], k = 3
<strong>Output: </strong>2
<strong>Explanation</strong>: Remove 4, 2 and either one of the two 1s or three 3s. 1 and 3 will be left.</pre>

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

<ul>
	<li><code>1 &lt;= arr.length&nbsp;&lt;= 10^5</code></li>
	<li><code>1 &lt;= arr[i] &lt;= 10^9</code></li>
	<li><code>0 &lt;= k&nbsp;&lt;= arr.length</code></li>
</ul>
class Solution {
public:
    int findLeastNumOfUniqueInts(vector<int>& arr, int k) {
        sort(arr.begin(),arr.end());
        vector <pair <int,int>> a;
        for (int i=0;i<arr.size();i++) {
            a.push_back(make_pair(1,arr[i]));
            if (i>0 && arr[i]==arr[i-1]) a[i].first=1+a[i-1].first;
        }

        for (int i=a.size()-2;i>=0;i--)
            if (a[i].second==a[i+1].second) a[i].first=a[i+1].first;

        sort(a.begin(),a.end());

        for (int i=0;i<a.size();i++)
            cout<<a[i].first<<" "<<a[i].second<<endl;

        int cnt=0;
        for (int j=k;j<a.size();j++)
            if (j==k || a[j].second!=a[j-1].second)
                cnt++;
        return cnt;
    }
};
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