#include <bits/stdc++.h>
using namespace std;
const int mod=1e9+7;
void add(int &x,int y){
    if((x+=y)>=mod)x-=mod;
}
const int N=1e6+10;
typedef long long ll;
const ll p1=31,p2=131;
const ll mod1=1e9+7,mod2=1e9+9;
typedef pair<ll,ll> hs;
const hs p = make_pair(p1,p2);
hs &operator+=(hs &a, hs b) {
    a.first=(a.first+b.first)%mod1;
    a.second=(a.second+b.second)%mod2;
    return a;
}
hs operator+(hs a, hs b) { return a += b; }
hs &operator-=(hs &a, hs b) {
    a.first=(a.first-b.first+mod1)%mod1;
    a.second=(a.second-b.second+mod2)%mod2;
    return a;
}
hs operator-(hs a, hs b) { return a -= b; }
hs &operator*=(hs &a, hs b) {
    a.first=(a.first*b.first)%mod1;
    a.second=(a.second*b.second)%mod2;
    return a;
}
hs operator*(hs a, hs b) { return a *= b; }
struct Hash{
    char st[N];
    int n;
    vector<hs>has1,has2,Pow;
    void Hash_init(string &s){
        n=(int)s.size();
        Pow.resize(n+2);
        has1.resize(n+2);
        has2.resize(n+2);
        Pow[0]=make_pair(1ll,1ll);
        for(int i=1;i<=n;i++)Pow[i]=Pow[i-1]*p;
        for(int i=1;i<=n;i++)has1[i]=has1[i-1]*p+hs{s[i-1]-'a'+1,s[i-1]-'a'+1};
        for(int i=n;i>=1;i--)has2[i]=has2[i+1]*p+hs{s[i-1]-'a'+1,s[i-1]-'a'+1};
    }
    hs get1(int l,int r){
        return has1[r]-has1[l-1]*Pow[r-l+1];
    }
    hs get2(int l,int r){
        return has2[l]-has2[r+1]*Pow[r-l+1];
    }
};
vector<vector<int>>dp1[1001],dp2[1001];
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    int n,L;
    cin>>n>>L;
    vector<Hash> a(n);
    vector<string>s(n);
    for(int i=0;i<n;i++){
        cin>>s[i];
        a[i].Hash_init(s[i]);
    }
    vector<int> zero(L+1);
    //1 前缀 2后缀 值是 分界线 [1-i]  [i-len]
    for(int i=1;i<=L;i++){
        dp1[i].resize(n);
        dp2[i].resize(n);
        for(int j=0;j<n;j++){
            dp1[i][j].resize((int)s[j].size()+1);
            dp2[i][j].resize((int)s[j].size()+1);
        }
    }
    zero[0]=1;
    for(int i=0;i<n;i++){
        int len=s[i].size();
        for(int j=1;j<=len;j++){//奇中心
            if(j>1&&j<len){
                int p1=j-1,p2=len-j;
                if(p1<p2){
                    if(a[i].get1(1,p1)==a[i].get2(j+1,j+p1)){
                        dp2[len][i][j+p1+1]++;
                    }
                }
                if(p1==p2){
                    if(a[i].get1(1,p1)==a[i].get2(j+1,j+p1)){
                        zero[len]++;
                    }
                }
                if(p1>p2){
                    if(a[i].get1(p1-p2+1,p1)==a[i].get2(j+1,len)){
                        dp1[len][i][p1-p2]++;
                    }
                }
            }
            else{
                if(j==1&&j+1<=len)dp2[len][i][2]++;
                if(j==len&&len-1>=1)dp1[len][i][len-1]++;
            }
        }
        for(int j=1;j<len;j++){//偶中心
            int p1=j,p2=len-j;
            if(p1<p2){
                if(a[i].get1(1,p1)==a[i].get2(j+1,j+p1)){
                    dp2[len][i][j+p1+1]++;
                }
            }
            if(p1==p2){
                if(a[i].get1(1,p1)==a[i].get2(j+1,j+p1)){
                    zero[len]++;
                }
            }
            if(p1>p2){
                if(a[i].get1(p1-p2+1,p1)==a[i].get2(j+1,len)){
                    dp1[len][i][p1-p2]++;
                }
            }
        }
        dp1[len][i][len]++;
    }
    
    auto check1 = [&](int i,int j,int k,int len2){// s[i][1-j]   with s[k] 
        //len2 = (int)s[k].size();
        // cout<<"i="<<i<<" j="<<j<<" k="<<k<<" len2="<<len2<<"\n";
        // if(j<=len2){
        //     cout<<a[i].get1(1,j).first<<" "<<a[k].get2(1,j).first<<"\n";
        // }
        if(j<=len2)return a[i].get1(1,j)==a[k].get2(1,j);
        else return a[i].get1(j-len2+1,j)==a[k].get2(1,len2);
    };
    auto check2 = [&](int i,int j,int k,int len2){// s[i][j-n]   with s[k] 
        //len2 = (int)s[k].size();
        int len=(int)s[i].size();
        if(len-j+1<=len2) return a[i].get1(j,len)==a[k].get2(len2-(len-j+1)+1,len2);
        else return a[i].get1(j,j+len2-1)==a[k].get2(1,len2);
    };
    for(int l=1;l<L;l++){
        for(int i=0;i<n;i++){
            int len=(int)s[i].size();
            if(l+len<=L)add(dp1[l+len][i][len],zero[l]);

            for(int j=1;j<=len;j++){
                if(dp1[l][i][j]){
                    // cout<<"dp1["<<l<<"]["<<i<<"]["<<j<<"]="<<dp1[l][i][j]<<"\n";
                    for(int k=0;k<n;k++)if(l+(int)s[k].size()<=L&&check1(i,j,k,(int)s[k].size())){
                        int len2=(int)s[k].size();
                        if(j<len2){
                            add(dp2[l+len2][k][j+1],dp1[l][i][j]);
                        }
                        if(j==len2){
                            add(zero[l+len2],dp1[l][i][j]);
                        }
                        if(j>len2){
                            add(dp1[l+len2][k][j-len2],dp1[l][i][j]);
                        }
                    }
                }
            }
            for(int j=1;j<=len;j++)if(dp2[l][i][j]){
                assert(j!=1);
                for(int k=0;k<n;k++)if(l+(int)s[k].size()<=L&&check2(i,j,k,(int)s[k].size())){
                    int len2=(int)s[k].size();
                    if(len-j+1<len2){
                        add(dp1[l+len2][k][len2-(len-j+1)],dp2[l][i][j]);
                    }
                    if(len-j+1==len2){
                        add(zero[l+len2],dp2[l][i][j]);
                    }
                    if(len-j+1>len2){
                        add(dp2[l+len2][k][j+len2],dp2[l][i][j]);
                    }
                }
            }
        }
    }
    cout<<zero[L]<<"\n";
    return 0;
}