#include <bits/stdc++.h>
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
//using namespace __gnu_pbds;

// #pragma GCC optimize("O3,unroll-loops")
// #pragma GCC target("avx2")
#define setp(x) cout<<fixed<<setprecision(x)
#define sz(x) (int)(x).size()
#define all(x) begin(x), end(x)
#define forn(i,a,b) for(int i=(a);i<(b);i++)
#define fore(i,a,b) for(int i=(a);i<=(b);i++)
#define pb push_back
#define F first
#define S second
#define fbo find_by_order
#define ook order_of_key
typedef long long ll;
typedef long double ld;
typedef pair<ll,ll> ii;
typedef vector<int> vi;
typedef vector<ii> vii;
//template<typename T>
//using pbds = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
void SD(int t=0){ cout<<"PASSED "<<t<<endl; }
template<typename T> void amax(T &a, T b){ a=max(a,b); }
template<typename T> void amin(T &a, T b){ a=min(a,b); }
struct Hash {
    static uint64_t splitmix64(uint64_t x) {
        // http://xorshift.di.unimi.it/splitmix64.c
        x += 0x9e3779b97f4a7c15;
        x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
        x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
        return x ^ (x >> 31);
    }
    size_t operator()(uint64_t x) const {
        static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
        return splitmix64(x + FIXED_RANDOM);
    }
};

const ll INF = ll(1e18);
const int MOD = 998244353;
const bool DEBUG = 0;
const int MAXN = 100005;
const int LG = 21;

vi Z(const string& S) {
	vi z(sz(S));
	int l = -1, r = -1;
	forn(i,1,sz(S)) {
		z[i] = i >= r ? 0 : min(r - i, z[i - l]);
		while (i + z[i] < sz(S) && S[i + z[i]] == S[z[i]])
			z[i]++;
		if (i + z[i] > r)
			l = i, r = i + z[i];
	}
	return z;
}

int main()
{
    cin.tie(0)->sync_with_stdio(0);

    int n,m; cin>>n>>m;
    vector<string> s(m);
    forn(i,0,m) cin>>s[i];

    int minlen = 2 * sz(s[0]) - n;

    vector<vi> mat(m);
    forn(id,0,m)
    {
        vi p = Z(s[id]);
        vi& r = mat[id];
        forn(i,1,sz(s[id]))
        {
            int len = sz(s[id]) - i;
            if (len < minlen) break;
            if (p[i] != len) continue;
            r.pb(len);
        }
    }

    vector<int> a(m);
    forn(i,0,m) a[i] = i;
    sort(all(a), [&mat](int i, int j){
        return make_pair(mat[i], i) < make_pair(mat[j], j);
    });
    forn(i,0,m) cout<<s[a[i]]<<'\n';

    return 0;
}