1 #include <iostream>
 2 #include<cstdio>
 3 #include<cstring>
 4 #include<algorithm>
 5 #include<stdlib.h>
 6 #include<vector>
 7 #include<queue>
 8 #include<vector>
 9 using namespace std;
10 #define INF 0xfffffff
11 #define N 1000010
12 char s[N];
13 int next[N];
14 int vis[N];
15 void kmp(int k)
16 {
17     int i,j=-1;
18     next[0] = -1;
19     for(i = 1 ; i < k ; i++)
20     {
21         while(j>-1&&s[i]!=s[j+1])
22         j = next[j];
23         if(s[i]==s[j+1])
24         j++;
25         next[i] = j;
26     }
27 }
28 int main()
29 {
30     //freopen("data.in","r",stdin);
31     //freopen("data1.out","w",stdout);
32     int n,i;
33     int kk=1;
34     cin>>n;
35     while(n--)
36     {
37         memset(vis,0,sizeof(vis));
38         memset(next,0,sizeof(next));
39         cin>>s;
40         int k = strlen(s);
41         kmp(k);
42         int len = next[k-1];
43         vis[len] = 1;
44         while(len!=-1)
45         {
46             vis[next[len]] = 1;
47             len = next[len];
48         }
49         int mm = 0;
50         for(i = 0 ; i < k-1 ; i++)
51         if(vis[next[i]]) mm = max(mm,next[i]+1);
52         if(mm)
53         {
54             for(i = 0 ;i < mm ; i++)
55             cout<<s[i];
56             puts("");
57         }
58         else
59         puts("Bad Luck!");
60     }
61     return 0;
62 }
63
64 /**************************************
65     Problem id    : SDUT OJ 2784
66     User name    : shang
67     Result        : Accepted
68     Take Memory    : 9240K
69     Take Time    : 180MS
70     Submit Time    : 2014-02-15 15:57:03
71 **************************************/