#include<bits/stdc++.h>
#define ALL(v) std::begin(v),std::end(v)
using lint=long long;
using lubl=long double;
lint mod=1'000'000'000;
struct mint{
    lint value;
    mint()=default;
    mint(lint x):value(x){}
};
std::ostream&operator<<(std::ostream&os,mint x){return os<<x.value;}
mint operator+(mint x,mint y){lint z=x.value+y.value;if(mod<=z)z-=mod;return z;}
mint&operator+=(mint&x,mint y){return x=x+y;}
int main(){
    std::cin.tie(nullptr);std::ios_base::sync_with_stdio(false);
    std::cout.setf(std::ios_base::fixed);std::cout.precision(15);
    lint a,b;std::cin>>a>>b;
    a/=1'000;
    a%=b;
    std::vector<std::vector<mint>>binom(b+1);
    binom.at(0)={1};
    for(lint i=0;i<b;i++){
        binom.at(i+1).resize(i+2);
        for(lint j=0;j<=i;j++){
            mint x=binom.at(i).at(j);
            binom.at(i+1).at(j)+=x;
            binom.at(i+1).at(j+1)+=x;
        }
    }
    std::cout<<binom.at(b).at(a)<<'\n';
}