Power Strings
Time Limit: 3000MS | Memory Limit: 65536K | |
Total Submissions: 23530 | Accepted: 9880 |
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
#include <cstdio> #include <cstring> using namespace std; char str[1000010]; int next[1000010]; int main() { int i,j; int len; int ans; while(scanf("%s",str)!=EOF) { if(!strcmp(str,".")) break; memset(next,0,sizeof(next)); //kmp -- getNext() i=-1; j=0; len=strlen(str); next[0]=-1; while(j<len) { if(i==-1 || str[i]==str[j]) { i++; j++; next[j]=i; } else { i=next[i]; } } ans=1; i=len-next[len]; if(len%i==0) { ans=len/i; } printf("%d\n",ans); } return 0; }