/* 4057 */

 #include <iostream>

 #include <sstream>

 #include <string>

 #include <map>

 #include <queue>

 #include <set>

 #include <stack>

 #include <vector>

 #include <deque>

 #include <algorithm>

 #include <cstdio>

 #include <cmath>

 #include <ctime>

 #include <cstring>

 #include <climits>

 #include <cctype>

 #include <cassert>

 #include <functional>

 #include <iterator>

 #include <iomanip>

 using namespace std;

 //#pragma comment(linker,"/STACK:102400000,1024000")

 #define sti                set<int>

 #define stpii            set<pair<int, int> >

 #define mpii            map<int,int>

 #define vi                vector<int>

 #define pii                pair<int,int>

 #define vpii            vector<pair<int,int> >

 #define rep(i, a, n)     for (int i=a;i<n;++i)

 #define per(i, a, n)     for (int i=n-1;i>=a;--i)

 #define clr                clear

 #define pb                 push_back

 #define mp                 make_pair

 #define fir                first

 #define sec                second

 #define all(x)             (x).begin(),(x).end()

 #define SZ(x)             ((int)(x).size())

 #define lson            l, mid, rt<<1

 #define rson            mid+1, r, rt<<1|1

 const int maxn = ;

 const int maxm = ;

 const int maxl = ;

 char s[maxl];

 int W[maxn];

 bool dp[][maxm][maxm];

 int n, m, l;

 typedef struct {

     static const int maxn = ;

     static const int rt = ;

     int nxt[maxn][];

     int fail[maxn];

     int f[maxn];

     int m;

     void init() {

         m = ;

         memset(f, , sizeof(f));

         memset(nxt, , sizeof(nxt));

     }

     int newNode() {

         return ++m;

     }    

     int getId(char c) {

         if (c == 'A')    return ;

         if (c == 'T')    return ;

         if (c == 'G')    return ;

         if (c == 'C')    return ;

         return -;

     }

     void Insert(char *s, int k) {

         int i = , id;

         int p = , q;

         while (s[i]) {

             id = getId(s[i]);

             q = nxt[p][id];

             if (!q)

                 q = nxt[p][id] = newNode();

             p = q;

             ++i;

         }

         f[p] |= ( << k);

     }

     void Build() {

         int cur;

         queue<int> Q;

         fail[rt] = rt;

         rep(i, , ) {

             if (nxt[rt][i] == ) {

                 nxt[rt][i] = rt;

             } else {

                 fail[nxt[rt][i]] = rt;

                 Q.push(nxt[rt][i]);

             }

         }

         while (!Q.empty()) {

             cur = Q.front();

             Q.pop();

             rep(i, , ) {

                 if (nxt[cur][i] == ) {

                     nxt[cur][i] = nxt[fail[cur]][i];

                 } else {

                     fail[nxt[cur][i]] = nxt[fail[cur]][i];

                     f[nxt[cur][i]] |= f[nxt[fail[cur]][i]];

                     Q.push(nxt[cur][i]);

                 }

             }

         }

     }

 } AC;

 AC ac;

 int calw(int x) {

     int ret = ;

     rep(i, , n) {

         if (x & (<<i))

             ret += W[i];

     }

     return ret;

 }

 void solve() {

     int ans = INT_MIN;

     int mst = <<n, nst, nxt;

     int p = , q = ;

     m = ac.m;

     memset(dp, , sizeof(dp));

     dp[][ac.rt][] = true;

     rep(i, , l+) {

         memset(dp[q], , sizeof(dp[q]));

         rep(j, , m+) {

             rep(k, , ) {

                 rep(st, , mst) {

                     if (dp[p][j][st]) {

                         nxt = ac.nxt[j][k];

                         nst = st | ac.f[nxt];

                         dp[q][nxt][nst] = true;

                     }

                 }

             }

         }

         p = q;

         q ^= ;

     }

     rep(st, , mst) {

         rep(j, , m+) {

             if (dp[p][j][st]) {

                 ans = max(ans, calw(st));

                 break;

             }

         }

     }

     if (ans < )

         puts("No Rabbit after 2012!");

     else

         printf("%d\n", ans);

 }

 int main() {

     ios::sync_with_stdio(false);

     #ifndef ONLINE_JUDGE

         freopen("data.in", "r", stdin);

         freopen("data.out", "w", stdout);

     #endif

     int len, w;

     while (scanf("%d %d",&n,&l) != EOF) {

         ac.init();

         rep(i, , n) {

             scanf("%s %d", s, &W[i]);

             ac.Insert(s, i);

         }

         ac.Build();

         solve();

     }

     #ifndef ONLINE_JUDGE

         printf("time = %d.\n", (int)clock());

     #endif

     return ;

 }