#include<iostream>

#include<cstdio>

#include<algorithm>

using namespace std;

//处理出来n的质因子中，x的个数。

int  prime(int n,int x)

{

    int res=;

    while(n) res+=n/x,n/=x;

    return res;

}

//f(1)到f(n)中不以5结尾的奇数的个数

int expect_5_end_odd(int n,int x)

{

    if(!n) return ;

    return n/+(n%>=x)+expect_5_end_odd(n/,x);

}

//以5结尾的数的个数。

int expect_5_end(int n,int x)

{

    if(!n) return ;

    return expect_5_end(n/,x)+expect_5_end_odd(n,x);

}

int t[][]={

    ,,,,//2^4 2 2^2 2^3 的最后一位

    ,,,,//3^4 3 3^2 3^3 的最后一位

    ,,,,//4……

    ,,,//5……

};

signed main()

{

    int n,m;

    while(~scanf("%d%d",&n,&m))

    {

        m=n-m;

        int prime_2=prime(n,)-prime(m,);

        int prime_3=expect_5_end(n,)-expect_5_end(m,);

        int prime_5=prime(n,)-prime(m,);

        int prime_7=expect_5_end(n,)-expect_5_end(m,);

        int prime_9=expect_5_end(n,)-expect_5_end(m,);

        if(prime_2<prime_5){puts("");continue;}

        int res=;

        if(prime_2>prime_5) res*=t[][(prime_2-prime_5)%];

        res=res*t[][prime_3%]*t[][prime_7%]*t[][prime_9%]%;

        printf("%lld\n",res);

    }

    return ;

}