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poj1961--Power Strings(kmp:求循环串的次数)

Power Strings
Time Limit: 3000MS Memory Limit: 65536K
Total Submissions: 33163 Accepted: 13784

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

abcdaaaaababab.

Sample Output

143

Hint

This problem has huge input, use scanf instead of cin to avoid time limit exceed.

Source

Waterloo local 2002.07.0
 
#include <cstdio>#include <cstring>#include <algorithm>int next[1100000] ;char str[1100000] ;void getnext(int l){    int j = 0 , k = -1 ;    next[0] = -1 ;    while(j < l)    {        if( k == -1 || str[j] == str[k] )        {            j++ ;            k++ ;            next[j] = k ;        }        else            k = next[k] ;    }}int main(){    int l , m ;    while(scanf("%s", str)!=EOF)    {        if( str[0] == '.' ) break;        l = strlen(str);        getnext(l) ;        m = next[l];        if( m == -1  )            printf("1\n");        else if(m == l)            printf("%d\n", l);        else if( l % (l-m) != 0 )            printf("1\n");        else        {            m = l / ( l-m );            printf("%d\n", m);        }        memset(str,0,sizeof(str));    }    return 0;}

poj1961--Power Strings(kmp:求循环串的次数)