#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; const constexpr int INF = 1e9; #define FOR(i, a, n) for (ll i = (ll)a; i<(ll)n; ++i) #define REP(i, n) FOR(i, 0, n) typedef long long ll; typedef vector VI; typedef pair P; struct Less{ bool operator()(const pair&a, const pair&b){ if(a.first==b.first){ return a.second < b.second; } return a.first < b.first; } }; const constexpr ll MOD = 1e9; ll extGCD(ll a, ll b, ll& x, ll& y){ if(b==0){ x=1; y=0; return a; } ll d = extGCD(b, a%b, y, x); y -= a/b*x; return d; } ll GCD(ll a, ll b){ if(b==0) return a; return GCD(b, a%b); } ll comb[10010][10010]; int main() { ll N, M; cin >> N >> M; ll r = (N - (((N/M)/1000)*1000*M))/1000; // ←ほんまか? for(int i=0; i<10010; ++i){ comb[i][0] = 1; comb[i][i] = 1; } for(int i=1; i<10010; ++i){ for(int j=1; j<10010; ++j){ comb[i][j] = ((comb[i-1][j-1]%MOD)+(comb[i-1][j]%MOD))%MOD; } } cout << comb[M][r] << endl; return 0; }