1 #include<cstdio>
 2 #include<algorithm>
 3 #include<cstring>
 4 #include<cmath>
 5 #include<iostream>
 6 #include<cctype>
 7 #include<set>
 8 #include<vector>
 9 #include<queue>
10 #include<map>
11 #define fi(s) freopen(s,"r",stdin);
12 #define fo(s) freopen(s,"w",stdout);
13 using namespace std;
14 typedef long long LL;
15 
16 inline int read() {
17     int x=0,f=1;char ch=getchar();for(;!isdigit(ch);ch=getchar())if(ch==‘-‘)f=-1;
18     for(;isdigit(ch);ch=getchar())x=x*10+ch-‘0‘;return x*f;
19 }
20 
21 const int N = 105;
22 const int C = 200005;
23 const int mod = 10007;
24 
25 char s[N];
26 int f[N][C], ch[C][26], val[C], fail[C], q[C], Index, n, m;
27 
28 void Insert(char *s) {
29     int u = 0, len = strlen(s + 1);
30     for (int i=1; i<=len; ++i) {
31         int c = s[i] - ‘A‘;
32         if (!ch[u][c]) ch[u][c] = ++Index;
33         u = ch[u][c];
34     }
35     val[u] = 1;
36 }
37 void build() {
38     int L = 1, R = 0; fail[0] = 0;
39     for (int c=0; c<26; ++c) {
40         int u = ch[0][c];
41         if (u) fail[u] = 0, q[++R] = u;
42     }
43     while (L <= R) {
44         int u = q[L ++];
45         for (int c=0; c<26; ++c) {
46             int v = ch[u][c];
47             if (!v) {
48                 ch[u][c] = ch[fail[u]][c]; continue; // !!!
49             }
50             q[++R] = v;
51             int p = fail[u];
52             while (p && !ch[p][c]) p = fail[p];
53             fail[v] = ch[p][c];
54             val[v] = val[v] ? val[v] : val[fail[v]];
55         }
56     }
57 }
58 void dp() {
59     f[0][0] = 1;
60     for (int i=0; i<m; ++i) {
61         for (int j=0; j<=Index; ++j) {
62             if (val[j] || !f[i][j]) continue;
63             for (int c=0; c<26; ++c) { // 不仅要走存在的，也要走不存在的点，存在的点不能走有标记的。 
64                 (f[i + 1][ch[j][c]] += f[i][j]) %= mod;
65             }
66         }
67     }
68 }
69 int main() {
70     n = read(), m = read();
71     for (int i=1; i<=n; ++i) {
72         scanf("%s", s + 1);
73         Insert(s);
74     }
75     build();
76     dp();
77     int ans = 1;
78     for (int i=1; i<=m; ++i) ans = (ans * 26) % mod;
79     for (int j=0; j<=Index; ++j) 
80         if (!val[j]) ans = (ans - f[m][j] + mod) % mod;
81     cout << ans;
82     return 0;
83 }