/*
    Authors
 Emilio Chavez Madero   A00816752
 Adrian Silva Mendez        A01281337

    Date    : 20/04/2017

    Description: PROYECTO DOS, RAILROAD
 */
#include <iostream>
#include <cmath>
#include <string>
#include <vector>
#include <algorithm>
#include <stack>
#include <queue>
#include <map>
#include <set>
#include <cstring>


using namespace std;
//----  definitions ----//
typedef vector<int> vi;

bool isPossible = false;
long long int tam1, tam2;
long long int v1[1001], v2[1001], v3[2000];
bool mat[1001][1001];

bool backtrackingSol(long long int pos1, long long int pos2, long long int len)
{
    if(pos1+pos2==len)
    {
        return true;
    }
    mat[pos1][pos2] = ((v1[pos1]==v3[pos1+pos2]&&mat[pos1+1][pos2]?backtrackingSol(pos1+1,pos2,len):false)||(v2[pos2]==v3[pos1+pos2]&&mat[pos1][pos2+1]?backtrackingSol(pos1,pos2+1,len):false));
    return mat[pos1][pos2];
}

//  ---- main ---- //
int main()
{
    long long int len1,len2,len3;
    fill(v1,v1+1001,-1);
    fill(v2,v2+1001,-1);
    while(1){
        memset(mat,true,1001*1001);
        // getting data
        cin >> len1 >> len2;
        tam1 = len1;
        tam2 = len2;

        if(!len1 && !len2)
            break;
        len3 = len1 + len2;

        // filling stacksi
        long long int temp;
        for(long long int i = 0; i<len1; i++){
            cin >> v1[i];
        }
        for(long long int i = 0; i<len2; i++){
            cin >> v2[i];
        }
        for(long long int i = 0; i<len3; i++)
        {
            cin >> v3[i];
        }
        // testing the sequence
        isPossible = backtrackingSol(0,0,len3);
        //cout << "out" << endl;

        if(isPossible)
            cout << "possible\n";
        else
            cout << "not possible\n";
    }


    return 0;

}