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POJ - 2406 Power Strings

int tdi and present sent span integer out instead

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. KMP的循環體問題
 1 #include<iostream>
 2 #include<cstdio>
 3 #include<algorithm>
 4 #include<cstring>
 5 
 6 using namespace std; 
 7 
 8 char s[1000005];
 9
int Next[1000005]; 10 11 void getnext(char* s,int m) 12 { 13 Next[0]=0; 14 Next[1]=0; 15 for(int i=1;i<m;i++) 16 { 17 int j=Next[i]; 18 while(j&&s[i]!=s[j]) 19 j=Next[j]; 20 if(s[i]==s[j]) 21 Next[i+1]=j+1; 22 else 23 Next[i+1]=0; 24 } 25 } 26 27 int main() 28 { 29 while(scanf("%s",s)) 30 { 31 if(s[0]==.&&s[1]==\0) 32 break; 33 memset(Next,0,sizeof(Next)); 34 int m=strlen(s); 35 getnext(s,m); 36 int x=1; 37 if(m%(m-Next[m])==0) 38 x=m/(m-Next[m]); 39 printf("%d\n",x); 40 } 41 42 43 return 0; 44 }

POJ - 2406 Power Strings