1 /**************************************************************
 2     Problem: 1030
 3     User: Tunix
 4     Language: C++
 5     Result: Accepted
 6     Time:208 ms
 7     Memory:7148 kb
 8 ****************************************************************/
 9  
10 //BZOJ 1030
11 #include<vector>
12 #include<cstdio>
13 #include<cstring>
14 #include<cstdlib>
15 #include<iostream>
16 #include<algorithm>
17 #define rep(i,n) for(int i=0;i<n;++i)
18 #define F(i,j,n) for(int i=j;i<=n;++i)
19 #define D(i,j,n) for(int i=j;i>=n;--i)
20 #define pb push_back
21 using namespace std;
22 inline int getint(){
23     int v=0,sign=1; char ch=getchar();
24     while(ch<‘0‘||ch>‘9‘){ if (ch==‘-‘) sign=-1; ch=getchar();}
25     while(ch>=‘0‘&&ch<=‘9‘){ v=v*10+ch-‘0‘; ch=getchar();}
26     return v*sign;
27 }
28 const int N=6010,INF=~0u>>2;
29 typedef long long LL;
30 /******************tamplate*********************/
31 const int MOD=10007;
32 int n,m,cnt=1;
33 struct Trie{
34     int ch[26],cnt,fail;
35     bool sign;
36 }T[N];
37 inline int id(char c){return c-‘A‘;}
38 void ins(char *s){
39     int x=1,y;
40     rep(i,strlen(s)){
41         y=id(s[i]);
42         if (T[x].ch[y]==0)
43             T[x].ch[y]=++cnt;
44         x=T[x].ch[y];
45     }
46     T[x].sign=1;
47 }
48 int Q[N];
49 void make_fail(){
50     int l=0,r=-1;
51     Q[++r]=1;
52     while(l<=r){
53         int x=Q[l++],y,j;
54         rep(i,26){
55             j=T[x].fail;
56             while(j && !T[j].ch[i]) j=T[j].fail;
57             if (T[x].ch[i]){
58                 y=T[x].ch[i];
59                 T[y].fail=j ? T[j].ch[i] : 1;
60                 T[y].sign=T[y].sign|T[T[y].fail].sign;
61                 Q[++r]=y;
62             }else T[x].ch[i]=j ? T[j].ch[i] : 1;
63         }
64     }
65 }
66 int f[110][N][2];
67 void dp(){
68     f[0][1][0]=1;
69     rep(i,m) F(j,1,cnt) rep(k,26) F(l,0,1)
70         if(T[T[j].ch[k]].sign) 
71             (f[i+1][T[j].ch[k]][1]+=f[i][j][l])%=MOD;
72         else (f[i+1][T[j].ch[k]][l]+=f[i][j][l])%=MOD;
73 }
74 char s[N];
75 int main(){
76 #ifndef ONLINE_JUDGE
77     freopen("1030.in","r",stdin);
78     freopen("1030.out","w",stdout);
79 #endif
80     n=getint(); m=getint();
81     F(i,1,n){
82         scanf("%s",s);
83         ins(s);
84     }
85     make_fail();
86     dp();
87     int ans=0;
88     F(i,1,cnt) (ans+=f[m][i][1])%=MOD;
89     printf("%d\n",ans);
90     return 0;
91 }