poj2752 Seek the Name, Seek the Fame

水题一枚：next函数应用
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 1 #include<stdio.h>
 2 #include<string.h>
 3 char str1[500005];
 4 int next[500005];
 5 int a[500005];
 6 void get_next(int x)
 7 {
 8     int i=0,j=-1;
 9     next[0]=-1;
10     while(i<x)
11     {
12         if(j==-1||str1[i]==str1[j])
13         {
14             i++;
15             j++;
16             //if(str1[i]!=str1[j])
17             next[i]=j;
18             //else next[i]=next[j];
19         }
20         else j=next[j];
21     }
22 }
23 
24 int main()
25 {
26     while(~scanf("%s",str1))
27     {
28         int len;
29         int len1=strlen(str1);
30         get_next(len1);
31         int k=0;
32         while(len1>0)
33         {
34             a[k++]=len1;
35             len1=next[len1];
36         }
37         for(int i=k-1;i>0;i--)
38         printf("%d ",a[i]);
39         printf("%d\n",a[0]);
40     }
41 }