#include <bits/stdc++.h>
#define _rep(i, x, y) for(int i = x; i <= y; ++i)
#define _req(i, x, y) for(int i = x; i >= y; --i)
#define _rev(i, u) for(int i = head[u]; i; i = e[i].nxt)
#define pb push_back
#define fi first
#define se second
#define mst(f, i) memset(f, i, sizeof f)
using namespace std;
#ifdef ONLINE_JUDGE
#define debug(...) 0
#else
#define debug(...) fprintf(stderr, __VA_ARGS__), fflush(stderr)
#endif
typedef long long ll;
typedef pair<int, int> PII;
namespace fastio{
    #ifdef ONLINE_JUDGE
    char ibuf[1 << 20],*p1 = ibuf, *p2 = ibuf;
    #define get() p1 == p2 && (p2 = (p1 = ibuf) + fread(ibuf, 1, 1 << 20, stdin), p1 == p2) ? EOF : *p1++
    #else
    #define get() getchar()
    #endif
    template<typename T> inline void read(T &t){
        T x = 0, f = 1;
        char c = getchar();
        while(!isdigit(c)){
            if(c == '-') f = -f;
            c = getchar();
        }
        while(isdigit(c)) x = x * 10 + c - '0', c = getchar();
        t = x * f;
    }
    template<typename T, typename ... Args> inline void read(T &t, Args&... args){
        read(t);
        read(args...);
    }
    template<typename T> void write(T t){
        if(t < 0) putchar('-'), t = -t;
        if(t >= 10) write(t / 10);
        putchar(t % 10 + '0');
    }
    template<typename T, typename ... Args> void write(T t, Args... args){
        write(t), putchar(' '), write(args...);
    }
    template<typename T> void writeln(T t){
        write(t);
        puts("");
    }
    template<typename T> void writes(T t){
        write(t), putchar(' ');
    }
    #undef get
};
using namespace fastio;
#define multitest() int T; read(T); _rep(tCase, 1, T)
namespace Calculation{
    const ll mod = 1e9 + 7, mod2 = 998244853;
    ll ksm(ll p, ll h){ll base = p % mod, res = 1; while(h){if(h & 1ll) res = res * base % mod; base = base * base % mod, h >>= 1ll;} return res;}
    void dec(ll &x, ll y){x = ((x - y) % mod + mod) % mod;}
    void add(ll &x, ll y){x = (x + y) % mod;}
    void add(int &x, int y){x = (x + y) % mod;}
    void mul(ll &x, ll y){x = x * y % mod;}
    ll sub(ll x, ll y){return ((x - y) % mod + mod) % mod;}
    ll pls(ll x, ll y){return ((x + y) % mod + mod) % mod;}
    ll mult(ll x, ll y){return x * y % mod;}
}
using namespace Calculation;
const int N = 1005, base = 13331;
int n, m, len, tlen[N];
int pre[N], suf[N], bel[N], pos[N];
char s[N][N], ch[N];
struct hashtable{
    int mod, pw[N];
    int pre[N], suf[N];
    void init(ll _mod, char *s){
        mod = _mod, pw[0] = 1;
        _rep(i, 1, len) pw[i] = 1ll * pw[i - 1] * base % mod, pre[i] = (1ll * pre[i - 1] * base + s[i]) % mod;
        reverse(s + 1, s + 1 + len);
        _rep(i, 1, len) suf[i] = (1ll * suf[i - 1] * base + s[i]) % mod;
        reverse(s + 1, s + 1 + len);
    }
    int getpre(int l, int r){return (pre[r] - 1ll * pre[l - 1] * pw[r - l + 1] % mod + mod) % mod;}
    int getsuf(int l, int r){return (suf[r] - 1ll * suf[l - 1] * pw[r - l + 1] % mod + mod) % mod;}
    int fuck[N][N];
    void work(){
        _rep(i, 1, len) _rep(j, i, len){
            int l = 0, r = min(len - i + 1, j), res = 0;
            while(l <= r){
                int mid = l + r >> 1;
                if(getpre(i, i + mid - 1) == getsuf(len - j + 1, len - (j - mid + 1) + 1)) res = mid, l = mid + 1;
                else r = mid - 1;
            }
            fuck[i][j] = res;
        }
    }
    bool check(int l, int r, int l2, int r2){
        if(l > l2) swap(l, l2), swap(r, r2);
        if(r - l + 1 != r2 - l2 + 1) return 0;
        return fuck[l][r2] >= r - l + 1;
    }
}hsh1, hsh2;
ll fl[N][N], fr[N][N], f[N];
int main(){
    read(n, m);
    _rep(i, 1, n){
        scanf("%s", s[i] + 1); tlen[i] = strlen(s[i] + 1);
        int t = len;
        _rep(j, 1, tlen[i]) ch[++len] = s[i][j], pre[len] = t + 1, suf[len] = t + tlen[i], bel[len] = i;
        pos[i] = len;
    }
    hsh1.init(1000000009, ch), hsh2.init(998244853, ch);
    hsh1.work(), hsh2.work();
    if(m & 1){
        _rep(i, 1, len){
            int l = pre[i], r = i - 1, L = i + 1, R = suf[i];
            int lenl = r - l + 1, lenr = R - L + 1;
            int cur = min(lenl, lenr);
            if(hsh1.check(i - cur, i - 1, i + 1, i + cur) && hsh2.check(i - cur, i - 1, i + 1, i + cur)){
                if(lenl < lenr) fr[lenl][i + cur + 1]++;
                if(lenl > lenr) fl[lenr][i - cur - 1]++;
                if(lenl == lenr) f[lenl]++;
            }
        }
    }else{
        f[0]++;
        _rep(i, 1, len){
            if(i == suf[i]) continue;
            int l = pre[i], r = i, L = i + 1, R = suf[i];
            int lenl = r - l + 1, lenr = R - L + 1;
            int cur = min(lenl, lenr);
            if(hsh1.check(i - cur + 1, i, i + 1, i + cur) && hsh2.check(i - cur + 1, i, i + 1, i + cur)){
                if(lenl < lenr) fr[lenl][i + cur + 1]++;
                if(lenl > lenr) fl[lenr][i - cur]++;
                if(lenl == lenr) f[lenl]++;
            }
        }
    }
    m /= 2;
    _rep(i, 0, m - 1){
        _rep(j, 1, n) if(tlen[j] <= m - i) add(fl[i][pos[j]], f[i]);
        _rep(j, 1, len){
            fl[i][j] %= mod, fr[i][j] %= mod;
            if(!fl[i][j] && !fr[i][j]) continue;
            _rep(k, 1, n){
                int lenl = j - pre[j] + 1, lenr = tlen[k];
                int cur = min(lenl, lenr);
                if(i + max(lenl, lenr) <= m && fl[i][j]){
                    if(hsh1.check(j - cur + 1, j, pre[pos[k]], pre[pos[k]] + cur - 1)){
                        if(lenl < lenr) (fr[i + cur][pre[pos[k]] + cur] += fl[i][j]);
                        if(lenl > lenr) (fl[i + cur][j - cur] += fl[i][j]);
                        if(lenl == lenr) (f[i + cur] += fl[i][j]);
                    }
                }
                lenl = tlen[k], lenr = suf[j] - j + 1;
                cur = min(lenl, lenr);
                if(i + max(lenl, lenr) <= m && fr[i][j]){
                    if(hsh1.check(pos[k] - cur + 1, pos[k], j, j + cur - 1)){
                        if(lenl < lenr) (fr[i + cur][j + cur] += fr[i][j]);
                        if(lenl > lenr) (fl[i + cur][pos[k] - cur] += fr[i][j]);
                        if(lenl == lenr) (f[i + cur] += fr[i][j]);
                    }
                }
            }
        }
    }
    writeln(f[m] % mod);
    return 0;
}