
import std.algorithm;
import std.conv;
import std.stdio;
import std.string;
import std.math;

void main()
{
	auto ab = readln.split.map!( to!int );
	
	auto add = ab[ 0 ] + ab[ 1 ];
	auto sub = ab[ 0 ] - ab[ 1 ];
	auto mul = ab[ 0 ] * ab[ 1 ];
	
	writeln( max( add, sub, mul ) );
}
