import java.util.*;
import java.util.Arrays;

public class Main{
        public static void main(String[] args){
                Scanner scanCnt = new Scanner(System.in);
                int N = scanCnt.nextInt();
                int M = scanCnt.nextInt();

                int Array[] = new int[M];

                int ans=0;

                for(int i = 0 ; i < N ; i++ ){
                        int K = scanCnt.nextInt();
                        for(int j = 0 ; j < K ; j++ ){
                                int num = scanCnt.nextInt();
                                for(int p=0 ; p < M ; p++){
                                        if(num==p+1){
                                                Array[p]+=1;
                                        }
                                }
                        }
                }
                for(int p=0 ; p < M ; p++){
                        if(Array[p]==N){
                                ans++;
                        }
                }

                System.out.println(ans);

        }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz