Power Strings

Power Strings
Time Limit: 3000MS
 
Memory Limit: 65536K
Total Submissions: 27403
 
Accepted: 11468
Description
Given two strings a and b we define a*b to be their concatenation. For example, if a = "abc" and b = "def" then a*b = "abcdef". If we think of concatenation as multiplication, exponentiation by a non-negative integer is defined in the normal way: a^0 = "" (the empty string) and a^(n+1) = a*(a^n).
Input
Each test case is a line of input representing s, a string of printable characters. The length of s will be at least 1 and will not exceed 1 million characters. A line containing a period follows the last test case.
Output
For each s you should print the largest n such that s = a^n for some string a.
Sample Input
abcd
aaaa
ababab
.
Sample Output
1
4
3
Hint
This problem has huge input, use scanf instead of cin to avoid time limit exceed.
Source
Waterloo local 2002.07.01
/**
                  , a^n=s a   n  。

 kmp next     ,next                。

   s  , s              next[len]  。

If len%(len-next[len])==0  len/(len-next[len])         ,         a。

    

1

2

3

4

5

6

7 len-next[len]
  len%(len-next[len])==0       s   7  7 6   。 1-6 2-7  6(2-7) 5(1-6)   ,
 5 7   ,         ……
**/
#include
#include
using namespace std;
#define maxn 1001000

char s[maxn];
int len, next[maxn];

void get_next()
{
    int i=0,j=-1;
    next[0]=-1;
    while(i

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