POJ 1961 KMP 求前缀循环节 位置及次数

#include
#include
#define N 1000100
char T[N];
int f[N], len;
void getFail(){
	f[0] = f[1] = 0;
	for(int i = 1; i < len; i++)
	{
		int j = f[i];
		while(j && T[i]!=T[j]) j = f[j];
		f[i+1] = T[i] == T[j]  j+1: 0;
	}
}

int main(){
	int Cas = 1;
	while(scanf("%d",&len), len){
		scanf("%s",T);
		printf("Test case #%d\n",Cas++);
		getFail();

		for(int i = 1; i <= len; i++)
		{
			int length = i - f[i];  //循环节长度
			if(i != length && i%length == 0)
				printf("%d %d\n", i, i/length);
		}
		printf("\n");
	}
	return 0;
}