Power Strings
Time Limit : 6000/3000ms (Java/Other) Memory Limit : 131072/65536K (Java/Other)
Total Submission(s) : 96 Accepted Submission(s) : 34
Problem 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
题目分析:
意思是有多少个子串构成比如说 aaaa = a^4 ababab=(ab)^3 abcd=(abcd)^1 应该明白了吧!也就是这个字符串能被他的最短子串构成 由kmp ,next表的特点知如果满足 len%(len-p[len])==0 就能由子串构成且子串个数就是 len/(len-p[len])
#include<cstdio> #include<cstring> const int M = 1000000+10; char str[M]; int p[M],a[M],len; void getp() { int i=0,j=-1; p[i]=j; while(i<len) { if(j==-1||str[i]==str[j]) { i++;j++; p[i]=j; } else j=p[j]; } } int main() { while(~scanf("%s",str)&&str[0]!='.') { len=strlen(str); getp(); if(len%(len-p[len])==0) printf("%d\n",len/(len-p[len])); else printf("1\n"); } return 0; }