#include <bits/stdc++.h> using namespace std; using ll = long long; using ull = unsigned long long; #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(x) (x).begin(),(x).end() #define MOD 1000000007 #define MOD2 998244353 #define INF 1000000007 #define LINF 1000000000000000007LL #define PI 3.14159265359 #define P pair<ll,ll> template <typename T> inline bool chmax(T &a, const T &b){ if(a<b) {a=b; return true;} else return false; } template <typename T> inline bool chmin(T &a, const T &b){ if(a>b) {a=b; return true;} else return false; } struct Edge{ int to; ll cost; Edge(int to, ll cost) : to(to), cost(cost) {} }; typedef vector<Edge> Edges; typedef vector<Edges> Graph; void add_edge(Graph &g,int from,int to,ll cost,bool rev,ll rev_cost){ g[from].push_back(Edge(to,cost)); if(rev) g[to].push_back(Edge(from,rev_cost)); } void solve(){ int a,b; cin>>a>>b; int OR = a|b; ll ans=1; while(OR>0){ ans*=OR; OR--; } cout<<ans<<'\n'; } int main(){ ios::sync_with_stdio(false); cin.tie(nullptr); cout<<setprecision(10)<<fixed; solve(); return 0; }