1 // File Name: temp.cpp
  2 // Author: darkdream
  3 // Created Time: 2014年09月11日 星期四 15时18分4秒
  4
  5 #include<vector>
  6 #include<list>
  7 #include<map>
  8 #include<set>
  9 #include<deque>
 10 #include<stack>
 11 #include<bitset>
 12 #include<algorithm>
 13 #include<functional>
 14 #include<numeric>
 15 #include<utility>
 16 #include<sstream>
 17 #include<iostream>
 18 #include<iomanip>
 19 #include<cstdio>
 20 #include<cmath>
 21 #include<cstdlib>
 22 #include<cstring>
 23 #include<ctime>
 24 #include<queue>
 25 #define LL long long
 26 #define maxn 1005
 27
 28 using namespace std;
 29 int dp[maxn][maxn];
 30 struct Trie
 31 {
 32     int next[maxn][4],fail[maxn],end[maxn];
 33     int root, L;
 34     int newnode()
 35     {
 36         memset(next[L],-1,sizeof(next[L]));
 37         end[L++] = 0 ;
 38         return L-1;
 39     }
 40     void init()
 41     {
 42         L = 0 ;
 43         root = newnode();
 44     }
 45     void insert(int buf[],int len)
 46     {
 47         int now = root;
 48         for(int i = 0 ;i < len ;i ++)
 49         {
 50             if(next[now][buf[i]] ==  -1)
 51             {
 52                 next[now][buf[i]] = newnode();
 53             }
 54             now = next[now][buf[i]];
 55         }
 56         end[now] = 1;
 57     }
 58     void build()
 59     {
 60         queue<int> Q;
 61         fail[root] = root;
 62         for(int i = 0;i < 4;i ++)
 63         {
 64             if(next[root][i] == -1)
 65             {
 66                 next[root][i] = root;  //指向root 是没有问题的，我们主要是通过end 数组对个数进行计数的。
 67             }else{
 68                 fail[next[root][i]] = root;
 69                 Q.push(next[root][i]);
 70             }
 71         }
 72         while(!Q.empty())
 73         {
 74             int now = Q.front();
 75             Q.pop();
 76             for(int i = 0 ;i < 4;i ++)
 77             {
 78                 if(next[now][i] == -1)
 79                 {
 80                     next[now][i] =  next[fail[now]][i];
 81                 }
 82                 else{
 83                     fail[next[now][i]] = next[fail[now]][i];
 84                     if(end[next[fail[now]][i]] == 1)
 85                         end[next[now][i]] = 1;
 86                     Q.push(next[now][i]);
 87                 }
 88             }
 89         }
 90     }
 91     void query(int buf[],int len,int ca)
 92     {
 93         //end[3] = 1;
 94         memset(dp,2,sizeof(dp));
 95         dp[0][0] = 0;
 96         for(int i = 0 ;i < len ;i ++)
 97         {
 98             for(int j = 0 ;j < L ;j ++ )
 99             {
100              if(dp[i][j] < len && end[j] != 1)
101                for(int s = 0 ;s < 4;s ++)
102                {
103                  if(end[next[j][s]] != 1)
104                  dp[i+1][next[j][s]] = min(dp[i+1][next[j][s]],dp[i][j] + (buf[i] == s?0:1));
105                }
106             }
107         }
108        int ans = dp[len][0];
109        for(int i = 0 ;i < L ;i ++)
110        {
111            if(end[i] != 1)
112            ans = min(dp[len][i],ans);
113        }
114        if(ans <= len)
115        {
116           printf("Case %d: %d\n",ca,ans);
117        }else{
118           printf("Case %d: -1\n",ca);
119        }
120
121     }
122 };
123 char buf[3000];
124 int  temp[3000];
125 Trie ac;
126 void change(int len)
127 {
128     for(int i = 0;i < len;i ++)
129     {
130        if(buf[i] == 'A')
131        {
132          temp[i] = 0 ;
133        }else if(buf[i] == 'T'){
134          temp[i] = 1;
135        }else if(buf[i] == 'G')
136        {
137           temp[i] = 2;
138        }else if(buf[i] == 'C')
139        {
140           temp[i] = 3;
141        }
142     }
143 }
144 int main(){
145     int n;
146     int ca= 0 ;
147     //freopen("in","r",stdin);
148     while(scanf("%d",&n) != EOF,n)
149     {
150         ca ++ ;
151         ac.init();
152         int len = strlen(buf);
153         for(int i =1 ;i <= n;i ++)
154         {
155           scanf("%s",buf);
156           len = strlen(buf);
157           change(len);
158           ac.insert(temp,len);
159         }
160         ac.build();
161         scanf("%s",buf);
162         len = strlen(buf);
163         change(len);
164         ac.query(temp,len,ca);
165     }
166     return 0;
167 }