厉害

respect bro

虽然看起来简单，但是我还是想了挺久的

#include<bits/stdc++.h>
using namespace std;

#define int long long
#define PII pair<int,int>
#define INF 1e9
const int N=1e6;

void slove(){
    int n;
    cin>>n;


    map<int,int> m;
    int a;
    for(int i=0;i<n;i++){
        cin>>a;
        m[a]++;
    }
    int x=0;
    while(m.count(x))x++;


    vector<int> dist(n+1,INF);
    vector<bool> flag(n+1);
    dist[x]=0;
    priority_queue<PII,vector<PII>,greater<PII>> q;
    q.push({0,x});

    while(q.size()){
        int u=q.top().second;
        q.pop();
        if(flag[u])continue;
        flag[u]=1;

        for(int i=u-1;i>=0;i--){
            if(dist[i]>dist[u]+m[i]*u){
               dist[i]=dist[u]+m[i]*u;
               q.push({dist[i],i});
            }
       }
    }
    cout<<dist[0]-x<<endl;
}

signed main(){
    int t;
    cin>>t;
    while(t--){
        slove();
    }
}