POJ - 2406 Power Strings(KMP 循环节)

#include <cstdio>
#include <cstring>
const int N = 1000010;
char str
;
int len;
int next
;

void getFail() {
len = strlen(str);
int i = 0, j = -1;
next[0] = -1;
while (i < len) {
if (j == -1 || str[i] == str[j]) {
i++; j++;
next[i] = j;
}
else j = next[j];
}
}

int main() {
while (scanf("%s", str) && str[0] != '.') {
getFail();
if (len % (len - next[len]) == 0)
printf("%d\n", len / (len - next[len]));
else printf("1\n");
}
return 0;
}