1 #include<stdio.h>
2 #include<string.h>
3 char c1[1000011],c2[1000011];
4 int next[1000011];
5 int kmp()
6 {
7 int k = strlen(c1),i,j,y = -1;
8 memset(next,0,sizeof(next));
9 next[0] = -1;
10 for(i = 1; i < k ;i ++)
11 {
12 while(y>-1&&c1[i]!=c1[y+1])
13 y = next[y];
14 if(c1[y+1]==c1[i])
15 y++;
16 next[i] = y;
17 }
18 int max = -1;
19 y = -1;
20 for(i = 0 ; i < k ; i++)
21 {
22 while(y>-1&&c2[i]!=c1[y+1])
23 y = next[y];
24 if(c1[y+1]==c2[i])
25 {
26 y++;
27 if(max<y)
28 max = y;
29 }
30 }
31 return max;
32 }
33 int main()
34 {
35 int t,n,m,i,j,k;
36 scanf("%d%*c", &t);
37 while(t--)
38 {
39 gets(c1);
40 k = strlen(c1);
41 for(i =0 ;i <= k-1 ;i++)
42 {
43 c2[i] = c1[k-i-1];
44 }
45 n = kmp();
46 for(i = n ; i >= 0 ; i--)
47 printf("%c", c1[i]);
48 puts("");
49 }
50 return 0;
51 }
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