import java.util.*;
import java.io.*;
class voters {
    public voters(String in) {
	StringTokenizer tok=new StringTokenizer(in," ");
	n=Integer.parseInt(tok.nextToken());
	ArrayList temp=new ArrayList();
	while(tok.hasMoreTokens())
	    temp.add(new Integer(Integer.parseInt(tok.nextToken())));
	pref=new int[temp.size()];
	for(int i=0;i<temp.size();i++)
	    pref[i]=((Integer)temp.get(i)).intValue()-1;
    }
    public int n;
    public int pref[];
}
public class election {
    public static void main(String args[]) {
	try {
	    BufferedReader br=new BufferedReader(new
						 InputStreamReader(System.in));
	    while(true) {
		StringTokenizer tok=new StringTokenizer(br.readLine()," ");
		int groups=Integer.parseInt(tok.nextToken());
		int n=Integer.parseInt(tok.nextToken());
		if(groups==0 && n==0) break;
		voters v[]=new voters[groups];
		for(int i=0;i<groups;i++) {
		    v[i]=new voters(br.readLine());
		}
		//solve
		boolean still[]=new boolean[n];
		for(int i=0;i<n;i++) still[i]=true;
		for(int it=0;it<n-1;it++) {
		    int votes[]=new int[n];
		    for(int i=0;i<v.length;i++) {
			for(int j=0;j<n;j++) {
			    if(still[v[i].pref[j]]) {
				votes[v[i].pref[j]]+=v[i].n;
				break;
			    }
			}
		    }
		    int worst=-1;
		    for(int i=0;i<n;i++) {
			if(!still[i]) continue;
			if(worst==-1 || votes[i]<=votes[worst])
			    worst=i;
		    }
		    still[worst]=false;
		}

		int winner=-1;
		for(int i=0;i<n;i++) {
		    if(still[i]) winner=i+1;
		}
		System.out.println(winner);
	    }
	}catch(Exception e) {
	    e.printStackTrace();
	}
    }
}