Power Strings
阿新 • • 發佈:2021-01-08
技術標籤:ACM
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 .
Output
1 4 3
Hint
This problem has huge input, use scanf instead of cin to avoid time limit exceed.
#include <stdio.h> #include <string.h> char s[1000001]; int next[1000001]; void getNext(int len) { int i=0,j=-1; next[0]=-1; while(i<len) { if(j==-1||s[i]==s[j])next[++i]=++j; else j=next[j]; } } int main() { while(scanf("%s",s)&&s[0]!='.') { int len=strlen(s); getNext(len); if(len%(len-next[len])==0) printf("%d\n",len/(len-next[len])); else printf("1\n"); } return 0; }