UVaLA 3026 Period MP算法

#include <cstdio>
#include <cstring>
#include <iostream>
using namespace std;

const int MAXN = 1000000 + 10;
char P[MAXN];
int n, f[MAXN];
//失配函数求 f 数组
void getFail()
{
f[0] = f[1] = 0;        //递推边界初值
for (int i = 1; i <= n; i++)
{
int j = f[i];
while (j && P[i] != P[j]) j = f[j];
f[i + 1] = P[i] == P[j] ? j + 1 : 0;
}
}

int main()
{
int kase = 0;
while (~scanf("%d", &n) && n)
{
scanf("%s", P);
getFail();

printf("Test case #%d\n", ++kase);
for (int i = 2; i <= n; i++)
if (f[i] > 0 && i % (i - f[i]) == 0)
printf("%d %d\n", i, i / (i - f[i]));

printf("\n");
}
return 0;
}