codeforce - candy box (easy version)

#include<bits/stdc++.h>
using namespace std;
#define fast()(ios_base::sync_with_stdio(0),cin.tie(NULL));
#define pb push_back
int main()
{
    fast();
    int q;
    cin>>q;
    while(q--)
    {
        map<int,int>mp,taken;
        vector<int>val,freq;
        int n,x,sum=0;
        cin>>n;
        for(int i=0;i<n;i++)
        {
            cin>>x;
            if(mp[x]==0)val.pb(x);
            mp[x]++;
        }
        for(int i=0;i<val.size();i++)
        {
            freq.pb(mp[val[i]]);

        }
        sort(freq.begin(),freq.end());
        x=freq[freq.size()-1];
        for(int i=freq.size()-1;i>=0;i--)
        {
            if(x==0)break;
            else if(taken[freq[i]]==0)
            {
                sum+=freq[i];
                taken[freq[i]]++;
                x=freq[i];
            }
            else
            {
                x--;
                taken[x]++;
                sum+=x;
            }
        }
        cout<<sum<<endl;
    }
}