package com.company;

import java.math.BigInteger;

import java.util.Scanner;

import static java.util.Arrays.copyOf;
import static java.util.Arrays.sort;

public class Main {

    public static void main(String[] args) {
        Scanner in=new Scanner(System.in);
      int n=in.nextInt(), m=in.nextInt();
        BigInteger ans=BigInteger.valueOf(1), count=BigInteger.valueOf(Math.min(n,m));

        for(int i=0; i<Math.max(m,n)&&count!=BigInteger.valueOf(0);i++){
           ans=ans.multiply(count);
           count=count.add(BigInteger.valueOf(-1));
        }
        System.out.println(ans);
    }

}