#include <iostream>
#include <fstream>
using namespace std;
ifstream in("multiplu.in"); ofstream out("multiplu.out");
int a,b,p;


int valid(int p)
{ int c, dif=0;
	while (p > 0)
	{
		c=p%10;
		if (c > 1) { dif=1; break; }
		p/=10;
	}
	
  if (dif==1) return 0; return 1;
}

int calculare(int p)
{ int i=1, aux;
  aux=p;
	for (;;)
	{
		p*=i; 
		i++; 
		if (valid(p)) break;
	    p=aux;
	}
	
	return p;
}

int main()
{
	in>>a>>b;
	
	p=a*b;
	
	out<<calculare(p);
	
	in.close();
	out.close();
return 0;	
}