#include using namespace std; #define rep(i,n) for(int i = 0; i < (int)(n); ++i) #define rrep(i,n) for(int i = (int)(n) - 1; i >= 0; --i) #define ALL(a) a.begin(), a.end() #define Sort(a) sort(a.begin(), a.end()) #define RSort(a) sort(a.rbegin(), a.rend()) typedef long long int ll; typedef long double ld; typedef vector vi; typedef vector vll; typedef vector vc; typedef vector vst; typedef vector vd; typedef pair P; const long long INF = 0x1fffffffffffffff; const long long MOD = 1000000007; const long double PI = acos(-1); template inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; } template inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; } template inline T vin(T& vec, U n) { vec.resize(n); for(int i = 0; i < (int) n; ++i) cin >> vec[i]; return vec; } template inline void vout(T vec, string s = "\n"){ for(auto x : vec) cout << x << s; } template void in(T&... a){ (cin >> ... >> a); } void out(){ cout << '\n'; } template void out(const T& a, const Ts&... b){ cout << a; (cout << ... << (cout << ' ', b)); cout << '\n'; } template void inGraph(vector>& G, U n, U m, bool directed = false){ G.resize(n); for(int i = 0; i < m; i++){ int a, b; cin >> a >> b; a--, b--; G[a].push_back(b); if(!directed) G[b].push_back(a); } } namespace Rho{ unsigned long long mul(unsigned long long a, unsigned long long b, const unsigned long long mod) { long long ret = a * b - mod * (unsigned long long)(1.0L / mod * a * b); return ret + mod * (ret < 0) - mod * (ret >= (long long) mod); } bool rabin_miller(unsigned long long n){ switch(n){ case 0: // fall-through case 1: return false; case 2: return true; } if(n % 2 == 0) return false; vector A = {2, 325, 9375, 28178, 450775, 9780504, 1795265022}; unsigned long long s = 0, d = n - 1; while(d % 2 == 0){ s++; d >>= 1; } auto modpow = [](unsigned long long x, unsigned long long e, const unsigned long long mod) -> unsigned long long { unsigned long long ret = 1 % mod; x %= mod; while(e > 0){ if(e & 1) ret = mul(ret, x, mod); x = mul(x, x, mod); e >>= 1; } return ret; }; for(auto a : A){ if(a % n == 0) return true; unsigned long long t, x = modpow(a, d, n); if(x != 1){ for(t = 0; t < s; ++t){ if(x == n - 1) break; x = mul(x, x, n); } if(t == s) return false; } } return true; } mt19937_64 rng(chrono::system_clock::now().time_since_epoch().count()); unsigned long long FindFactor(unsigned long long n) { if(n == 1 || rabin_miller(n)) return n; if(n % 2 == 0) return 2; unsigned long long c = 1, x = 0, y = 0, t = 0, prod = 2, x0 = 1, q; auto f = [&](unsigned long long X) { return mul(X, X, n) + c;}; while (t++ % 128 or __gcd(prod, n) == 1) { if(x == y) c = rng() % (n-1) + 1, x = x0, y = f(x); if((q = mul(prod, max(x, y) - min(x, y), n))) prod = q; x = f(x), y = f(f(y)); } return __gcd(prod, n); } vector factorize(unsigned long long x) { if(x == 1) return {}; unsigned long long a = FindFactor(x), b = x / a; if(a == x) return {a}; vector L = factorize(a), R = factorize(b); L.insert(L.end(), R.begin(), R.end()); return L; } vector divisor(unsigned long long x){ vector factor = Rho::factorize(x); map countFactor; for(auto x : factor){ if(countFactor.count(x) == 0) countFactor[x] = 0; countFactor[x]++; } vector ret = {1}; for(auto [x, cnt] : countFactor){ vector tmp; for(auto y : ret){ unsigned long long z = y; for(int i = 0; i < cnt + 1; i++){ tmp.push_back(z); z *= x; } } ret = tmp; } return ret; } } template T modpow(T x, T n, const T &m){ T ret = 1 % m; x %= m; while(n > 0){ if(n & 1) (ret *= x) %= m; (x *= x) %= m; n >>= 1; } return ret; } ll m, n; void input(){ in(m, n); } void solve(){ if(m < n){ out("00000000"); return; } ll mod = 100000000; n = min(n, m - n); ll mn = m - n + 1; vector mul(m + 1); for(int i = mn; i <= m; i++){ vector r = Rho::factorize(i); for(auto x : r){ mul[x]++; } } for(int i = 1; i <= n; i++){ vector r = Rho::factorize(i); for(auto x : r){ mul[x]--; } } ll ans = 1; for(ll i = 2; i <= m; i++){ if(mul[i] >= 1){ ans *= modpow(i, mul[i], mod); ans %= mod; } } string ans2 = to_string(ans); while(ans2.size() < 8){ ans2 = '0' + ans2; } out(ans2); } int main(){ ios::sync_with_stdio(false); cin.tie(nullptr); input(); solve(); }