#include using namespace std; #define ll long long #define rep(i,n) for(int i=0;i #define Tp tuple #define all(v) v.begin(),v.end() #define riano_ std::ios::sync_with_stdio(false);std::cin.tie(nullptr) using Graph = vector>; const ll mod = 8e18; template struct modint{ uint64_t val; constexpr modint(const int64_t val_=0) noexcept:val((val_%int64_t(mod)+int64_t(mod))%int64_t(mod)){} constexpr modint operator-() const noexcept{ return modint(*this)=mod-val; } constexpr modint operator+(const modint rhs) const noexcept{ return modint(*this)+=rhs; } constexpr modint operator-(const modint rhs) const noexcept{ return modint(*this)-=rhs; } constexpr modint operator*(const modint rhs) const noexcept{ return modint(*this)*=rhs; } constexpr modint operator/(const modint rhs) const noexcept{ return modint(*this)/=rhs; } constexpr modint &operator+=(const modint rhs) noexcept{ val+=rhs.val; val-=((val>=mod)?mod:0); return (*this); } constexpr modint &operator-=(const modint rhs) noexcept{ val+=((val>=1; } return (*this)*=now; } modint & operator++(){ val++; if (val == mod) val = 0; return *this; } modint operator++(int){ modint res = *this; ++*this; return res; } constexpr bool operator==(const modint rhs) noexcept{ return val==rhs.val; } constexpr bool operator!=(const modint rhs) noexcept{ return val!=rhs.val; } friend constexpr ostream &operator<<(ostream& os,const modint x) noexcept{ return os<<(x.val); } friend constexpr istream &operator>>(istream& is,modint& x) noexcept{ uint64_t t; is>>t,x=t; return is; } }; typedef modint mint; //Combination2 //10^6くらいまで //modはグローバルに定義しておく long long modinv(long long a, long long m) { long long b = m, u = 1, v = 0; while (b) { long long t = a / b; a -= t * b; swap(a, b); u -= t * v; swap(u, v); } u %= m; if (u < 0) u += m; return u; } vector fact; vector invf; ll comb(ll n,ll k){ if(n<0||k<0||k>n) return 0LL; else{ ll a = fact[n]*invf[k]%mod; a = a*invf[n-k]%mod; return a; } } int main() { riano_; ll ans = 0; //main関数内に以下ペースト //N:max ll N = 30; fact.assign(N+1,1LL); invf.assign(N+1,1LL); rep(i,N) fact[i+1] = fact[i]*(i+1)%mod; rep(i,N+1) invf[i] = modinv(fact[i],mod); ll a,b; cin >> a >> b; ans = fact[(a|b)]; cout << ans << endl; }