#include using namespace std; // 基本テンプレート struct cww{cww(){ios::sync_with_stdio(false);cin.tie(0);}}star; #define P(x) cout << (x) << endl #define p(x) cout << (x) #define all(c) (c).begin(), (c).end() #define rall(c) (c).rbegin(), (c).rend() #define mat(type, c, m, n) vector> c(m, vector(n));for(auto& r:c)for(auto& i:r)cin>>i; #define rep(i,a,n) for(int i=(a), i##_len=(n); in; --i) #define each(x,y) for(auto &(x):(y)) #define perm(c) sort(all(c));for(bool c##p=1;c##p;c##p=next_permutation(all(c))) #define cauto const auto& #define UNIQUE(v) v.erase( unique(all(v)), v.end() ); #define len(x) ((int)(x).size()) #define length(a) (sizeof(a)/sizeof(a[0])) #define mp make_pair #define eb emplace_back template inline bool inside(T y, T x, T h, T w) { return 0 <= y && y < h && 0 <= x && x < w; }; template inline bool chmin(T &a, const T &b){if (b < a) {a = b; return true;} return false; } template inline bool chmax(T &a, const T &b){if (a < b) {a = b; return true;} return false; } // デバッグ用 template inline void print(T t){cout << t << endl;} template inline void print(H h, T... t){cout << h << " ";print(t...);} #define dbg(v) for(auto i : v) { cout << i << " "; } cout << endl; // 型 typedef long long ll; typedef vector vi; typedef vector vd; typedef vector vll; typedef vector vs; typedef vector vb; // 定数 #define PI acos(-1.0) //constexpr int EPS = (1e-9); //constexpr int INF = 100000000; // 4近傍 //constexpr int dx[] = {1, 0, -1, 0}; //constexpr int dy[] = {0, 1, 0, -1}; // 8近傍 //constexpr int dy[]={0,0,1,-1,1,1,-1,-1}; //constexpr int dx[]={1,-1,0,0,1,-1,1,-1}; constexpr int mod = 1000000000; typedef unsigned long long ull; inline ull nCr(int n, int r, int dup = 0) { ull* a = (ull *)calloc(n,sizeof(ull)); int nn = (dup) ? (n + r - 1) : n; if(nn - r < r) r = nn - r; if(r == 0) return 1; if(r == 1) return nn; rep(i, 1, r) a[i] = i + 2; rep(i, 3, nn - r + 2) { a[0] = i; rep(j, 1, r) a[j] += a[j - 1] % mod; } ull retv = a[r - 1]; free(a); return retv % mod; } int main() { // cout << setprecision(15) << fixed; ll n, k; cin >> n >> k; n = n % (k * 1000) / 1000; P(nCr(k, n)); return 0; }