#include <cstdio>
#include <cstring>
#include <algorithm>
int main()
{
	int a, b;
	scanf("%d %d",&a,&b);
	int c = a+b;
	int d = a-b;
	int e = a*b;
	if(c>=d && d>=e) printf("%d\n",c);
	else if(d>=c && d>=e) printf("%d\n",d);
	else	printf("%d\n",d);
	
	
	
	
	return 0;
}