#include<iostream>
#include<vector>
using namespace std;

template<class T>
void sort_elem(T first,T last)
{
    T temp,temp1;
    for(temp=first;temp!=last-1;temp++)
    {
        for(temp1=temp;temp1!=last-1;temp1++)
        {
            if(*temp1>*(temp1+1))
            {
              int tmp;
              tmp=*temp1;
              *temp1=*(temp1+1);
              *(temp1+1)=tmp;
            }
        }
    }
}
int main(void)
{
    int n,m;
    while(cin>>n>>m,n!=0 || m!=0)
    {
        if(n>=0 && n<=100 && m>=0 && m<=100)
        {
        vector<int>set1,set2;
        int temp;
        while(n--)
        {            
            cin>>temp;
            set1.push_back(temp);
        }
        while(m--)
        {
            cin>>temp;
            set2.push_back(temp);
        }
        vector<int>::iterator ix1,ix2;
        for(ix1=set1.begin();ix1!=set1.end();)
        {
            for(ix2=set2.begin();ix2!=set2.end();ix2++)
            {
                if(*ix1==*ix2)
                {
                    ix1=set1.erase(ix1);
                    break;
                }
            }
            if(ix2==set2.end())
            {
                ix1++;
            }
        }
        if(!set1.empty())
        {
        sort_elem(set1.begin(),set1.end());
    
        for(ix1=set1.begin();ix1!=set1.end();ix1++)
        {
            cout<<*ix1<<" ";
        }
        cout<<endl;
        }
        else
        {
            cout<<"NULL"<<endl;
        }

    }
    }
    return 0;
}
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