#include #include #define MAX 40 #define MOD 10007 char dir[MAX]; int hash[256],n,m,total; struct node { int flag,in; node *fail,*next[4]; }*qu[MAX*MAX],arr[MAX*MAX],*root; node *CreateNode() { node *p = &arr[total]; p->in = total++; p->flag = 0; p->fail = NULL; for (int i = 0; i < 4; ++i) p->next[i] = NULL; return p; } void Insert(char *str) { int i = 0,k; node *p = root; while (str[i]) { k = hash[str[i++]]; if (p->next[k] == NULL) p->next[k] = CreateNode(); p = p->next[k]; } p->flag = 1; } void Build_AC() { int head,tail,i; head = tail = 0; root->fail = root; qu[++head] = root; while (tail < head) { node *p = qu[++tail]; for (i = 0; i < 4; ++i) { if (p->next[i] != NULL) { if (p == root) p->next[i]->fail = root; else p->next[i]->fail = p->fail->next[i]; qu[++head] = p->next[i]; p->next[i]->flag |= p->fail->next[i]->flag; } else { if (p == root) p->next[i] = root; else p->next[i] = p->fail->next[i]; }//else }//for }//while }//void struct Mat{ int mat[MAX*2][MAX*2],size; Mat(int n) {size = n,memset(mat,0,sizeof(mat));} Mat(int arr[][MAX*2],int n) { size = n,memcpy(mat,arr,sizeof(arr));} friend Mat operator *(Mat a,Mat b); friend Mat operator +(Mat a,Mat b); friend Mat operator ^(Mat a,int k); friend Mat Sum(Mat a,int k); }A(MAX*2),E(MAX*2); Mat operator *(Mat a,Mat b) { Mat c(total*2); for (int i = 0; i < c.size; ++i) for (int j = 0; j < c.size; ++j) for (int k = 0; k < c.size; ++k) if (a.mat[i][k] && b.mat[k][j]) { c.mat[i][j] += a.mat[i][k] * b.mat[k][j]; c.mat[i][j] %= MOD; } return c; } Mat operator +(Mat a,Mat b) { Mat c(total*2); for (int i = 0; i < c.size; ++i) for (int j = 0; j < c.size; ++j) c.mat[i][j] = (a.mat[i][j] + b.mat[i][j]) % MOD; return c; } Mat operator ^(Mat a,int k) { Mat c = E; while (k) { if (k & 1) c = c * a; a = a * a,k >>= 1; } return c; } Mat Sum(Mat A,int k) { if (k == 1) return A; else if (k & 1) return (A^k) * Sum(A,k-1); else return Sum(A,k/2) * ((A^(k/2)) + E); } void GetMat() { int i,j,k; Mat c(total*2); for (i = 0; i < total; ++i) { for (k = 0; k < 4; ++k) { j = arr[i].next[k]->in; if (arr[i].next[k]->flag) c.mat[i][j+total]++; else c.mat[i][j]++,c.mat[i+total][j+total]++; } } E = A = c; memset(E.mat,0,sizeof(E.mat)); for (i = 0; i < E.size; ++i) E.mat[i][i] = 1; } int Solve_1A() { int i,j,k,ans,sum; ans = 1,k = n,sum = 4; while (k) { if (k & 1) ans = (ans * sum) % MOD; sum = (sum * sum) % MOD,k >>= 1; } A = A^n; for (i = 0; i < 2 * total; ++i) ans = (ans - A.mat[0][i] + MOD) % MOD; return ans; } int main() { int i,j,k,ans; hash['A'] = 0,hash['T'] = 1; hash['C'] = 2,hash['G'] = 3; while (scanf("%d%d",&m,&n) != EOF) { total = 0; root = CreateNode(); for (i = 0; i < m; ++i) scanf("%s",dir),Insert(dir); Build_AC(); GetMat(); ans = Solve_1A(); printf("%d\n",ans % MOD); } }