//#pragma comment(linker, "/STACK:102400000")
#include<cstdlib>
#include<iostream>
#include<cstdio>
#include<cmath>
#include<cstring>
#include<algorithm>
#include<set>
#include<map>
#include<list>
#include<queue>
#include<stack>
#include<vector>
#define tree int o,int l,int r
#define lson o<<1,l,mid
#define rson o<<1|1,mid+1,r
#define lo o<<1
#define ro o<<1|1
#define pb push_back
#define mp make_pair
#define ULL unsigned long long
#define inf 0x7fffffff
#define eps 1e-7
#define N 35
#define M 26
using namespace std;
//void print2(ULL ma[][N],int n,int m)
//{
//    cout<<"=============="<<endl;
//    for (int i=0; i<n ; i++ )
//    {
//        printf("%d",ma[i][0]);
//        for (int j=1; j<m ; j++)
//            printf(" %d",ma[i][j]);
//        cout<<endl;
//    }
//    cout<<"-----------"<<endl;
//}int m,n,T,t,x,y,u;
int ch[N][M];
int v[N];
int f[N],last[N],num;
ULL ma[N][N],temp[N][N],sum[N][N],sum2[N][N],ans;
ULL he,maxv;
void clear()//Trie树初始化
{num=1;memset(ma,0,sizeof(ma));memset(sum,0,sizeof(sum));memset(ch[0],0,sizeof(ch[0]));memset(v,0,sizeof(v));memset(last,0,sizeof(last));
}
int idx(char c)
{return c-'a';
}
void insert(char str[],int value)//建Trie树
{int len=strlen(str);int u=0;for (int i=0; i<len; ++i ){int c=idx(str[i]);if(!ch[u][c])//保存的是结点坐标
        {memset(ch[num],0,sizeof(ch[num]));ch[u][c]=num++;//
        }u=ch[u][c];}v[u]=value;
}
void getac()
{queue<int> q;//保存的节点下标f[0]=0;for (int c=0; c<M; ++c ){int u=ch[0][c];if(u)//不需要优化的else
        {q.push(u);f[u]=0;last[u]=v[u];//WA
        }}while(!q.empty()){int r=q.front();q.pop();for (int c=0; c<M; ++c )//注意：c表示节点值，不是结点位置
        {int u=ch[r][c];if(u){q.push(u);int s=f[r];
//                while(s&&ch[s][c]==0)s=f[s];//可以简化f[u]=ch[s][c];last[u]=(v[u]||last[f[u]]);////
//                last[u]=v[f[u]]?f[u]:last[f[u]];
            }else //重要优化ch[r][c]=ch[f[r]][c];}}
}
char str[20];
void build()
{for(int i=0; i<num; i++){for(int j=0; j<M; j++){int u=ch[i][j];if(last[u]==0)ma[i][u]++;}}
}
void multi(ULL a[][N],ULL b[][N],int n)
{ULL c[N][N]= {0};for(int i=0; i<n; i++)for(int j=0; j<n; j++)for(int k=0; k<n; k++){c[i][j]+=a[i][k]*b[k][j];}memcpy(a,c,sizeof(c));
}
void mat(int n,int num)
{if(n==1){for(int i=0; i<num; i++)for(int j=0; j<num; j++)sum[i][j]=temp[i][j]=ma[i][j];he=maxv=26;}else{mat(n/2,num);memcpy(sum2,sum,sizeof(sum));multi(sum,temp,num);for(int i=0; i<num; i++)for(int j=0; j<num; j++)sum[i][j]+=sum2[i][j];multi(temp,temp,num);ULL hhh=he;he*=maxv;he+=hhh;maxv*=maxv;if(n&1){maxv*=26;he+=maxv;multi(temp,ma,num);for(int i=0; i<num; i++)for(int j=0; j<num; j++)sum[i][j]+=temp[i][j];}}
}
int main()
{
#ifndef ONLINE_JUDGEfreopen("ex.in","r",stdin);
#endifint ncase=0;while(scanf("%d%d%*c",&m,&n)==2){clear();while(m--){scanf("%s",str);insert(str,1);}getac();build();ans=0;mat(n,num);for(int i=0; i<num; i++){ans+=sum[0][i];}printf("%I64u\n",he-ans);//%I64u
    }return 0;
}