import java.util.Scanner;

public class Main {
	
	  
	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		while(in.hasNext()) {
			int a = in.nextInt();
			int b = in.nextInt();
			int ans = Math.max(Math.max(a+b, a-b), a*b);
			System.out.println(ans);
		}
	}
} import java.util.Scanner; Scanner java.util public class Main {
	
	  
	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		while(in.hasNext()) {
			int a = in.nextInt();
			int b = in.nextInt();
			int ans = Math.max(Math.max(a+b, a-b), a*b);
			System.out.println(ans);
		}
	}
} Main public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		while(in.hasNext()) {
			int a = in.nextInt();
			int b = in.nextInt();
			int ans = Math.max(Math.max(a+b, a-b), a*b);
			System.out.println(ans);
		}
	} main {
		Scanner in = new Scanner(System.in);
		while(in.hasNext()) {
			int a = in.nextInt();
			int b = in.nextInt();
			int ans = Math.max(Math.max(a+b, a-b), a*b);
			System.out.println(ans);
		}
	} Scanner in = new Scanner(System.in); in new Scanner(System.in) while(in.hasNext()) {
			int a = in.nextInt();
			int b = in.nextInt();
			int ans = Math.max(Math.max(a+b, a-b), a*b);
			System.out.println(ans);
		} in.hasNext() in.hasNext in {
			int a = in.nextInt();
			int b = in.nextInt();
			int ans = Math.max(Math.max(a+b, a-b), a*b);
			System.out.println(ans);
		} int a = in.nextInt(); a in.nextInt() in.nextInt in int b = in.nextInt(); b in.nextInt() in.nextInt in int ans = Math.max(Math.max(a+b, a-b), a*b); ans Math.max(Math.max(a+b, a-b), a*b) Math.max Math Math.max(a+b, a-b) Math.max Math a+b a b a-b a b a*b a b System.out.println(ans) System.out.println System.out System System.out ans String[] args args public class Main {
	
	  
	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		while(in.hasNext()) {
			int a = in.nextInt();
			int b = in.nextInt();
			int ans = Math.max(Math.max(a+b, a-b), a*b);
			System.out.println(ans);
		}
	}
} public class Main {
	
	  
	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		while(in.hasNext()) {
			int a = in.nextInt();
			int b = in.nextInt();
			int ans = Math.max(Math.max(a+b, a-b), a*b);
			System.out.println(ans);
		}
	}
} Main
import java.util.Scanner;

public class Main {
	
	  
	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		while(in.hasNext()) {
			int a = in.nextInt();
			int b = in.nextInt();
			int ans = Math.max(Math.max(a+b, a-b), a*b);
			System.out.println(ans);
		}
	}
}