import java.io.*;
import java.util.*;

class Main
{
    public static void main(String args[])throws Exception
    {
        BufferedReader bu=new BufferedReader(new InputStreamReader(System.in));
        StringBuilder sb=new StringBuilder();
        String s[]=bu.readLine().split(" ");
        int n=Integer.parseInt(s[0]),k=Integer.parseInt(s[1]);

        int i,b[]=new int[n];
        long dp[]=new long[n];
        for(i=0;i<n;i++)
        {
            s=bu.readLine().split(" ");
            int c=Integer.parseInt(s[0]),m=Integer.parseInt(s[1]);
            b[i]=c;
            if(i>0) dp[i]=dp[i-1];

            int j,x;
            s=bu.readLine().split(" ");
            for(j=0;j<m;j++)
            {
                x=Integer.parseInt(s[j])-1;
                dp[i]=Math.max(dp[x]+c-b[x],dp[i]);
            }
            //System.out.println(dp[i][0]+" "+dp[i][1]);
        }
        System.out.println(dp[n-1]);
    }
}