#include<cstdio>
#define MOD 123457
int N,K,a[510],b[510],*A,*B,*aux,i,j,SOL;
int main()
{
    freopen("mugur.in","r",stdin);
    freopen("mugur.out","w",stdout);
    scanf("%d%d",&N,&K);
    A=a;B=b;
    A[0]=0;
    A[1]=1;
    for(i=2;i<=N;i++)
    {
        for(j=1;j<=i;j++)
        {
            if(j==1)B[j]=A[i-1]; else
            B[j]=B[j-1]+A[i-1]-A[j-2];
            B[j]%=MOD;
        }
        aux=A;A=B;B=aux;
    }
    SOL=A[K]-A[K-1];
    if(SOL<0)SOL+=MOD;
    printf("%d\n",SOL);
    return 0;
}