import java.util.Scanner;

public class Main {
	static Scanner scan = new Scanner(System.in);
	
	public static void main(String[] args) {
		int a = scan.nextInt();
		int b = scan.nextInt();
		
		int n1 = a-b;
		int n2 = a+b;
		int n3 = a*b;
		
		int m = Math.max(n1, n2);
		m = Math.max(m, n3);
		
		System.out.println(m);
	}

} import java.util.Scanner; Scanner java.util public class Main {
	static Scanner scan = new Scanner(System.in);
	
	public static void main(String[] args) {
		int a = scan.nextInt();
		int b = scan.nextInt();
		
		int n1 = a-b;
		int n2 = a+b;
		int n3 = a*b;
		
		int m = Math.max(n1, n2);
		m = Math.max(m, n3);
		
		System.out.println(m);
	}

} Main static Scanner scan = new Scanner(System.in); scan new Scanner(System.in) public static void main(String[] args) {
		int a = scan.nextInt();
		int b = scan.nextInt();
		
		int n1 = a-b;
		int n2 = a+b;
		int n3 = a*b;
		
		int m = Math.max(n1, n2);
		m = Math.max(m, n3);
		
		System.out.println(m);
	} main {
		int a = scan.nextInt();
		int b = scan.nextInt();
		
		int n1 = a-b;
		int n2 = a+b;
		int n3 = a*b;
		
		int m = Math.max(n1, n2);
		m = Math.max(m, n3);
		
		System.out.println(m);
	} int a = scan.nextInt(); a scan.nextInt() scan.nextInt scan int b = scan.nextInt(); b scan.nextInt() scan.nextInt scan int n1 = a-b; n1 a-b a b int n2 = a+b; n2 a+b a b int n3 = a*b; n3 a*b a b int m = Math.max(n1, n2); m Math.max(n1, n2) Math.max Math n1 n2 m = Math.max(m, n3) m Math.max(m, n3) Math.max Math m n3 System.out.println(m) System.out.println System.out System System.out m String[] args args public class Main {
	static Scanner scan = new Scanner(System.in);
	
	public static void main(String[] args) {
		int a = scan.nextInt();
		int b = scan.nextInt();
		
		int n1 = a-b;
		int n2 = a+b;
		int n3 = a*b;
		
		int m = Math.max(n1, n2);
		m = Math.max(m, n3);
		
		System.out.println(m);
	}

} public class Main {
	static Scanner scan = new Scanner(System.in);
	
	public static void main(String[] args) {
		int a = scan.nextInt();
		int b = scan.nextInt();
		
		int n1 = a-b;
		int n2 = a+b;
		int n3 = a*b;
		
		int m = Math.max(n1, n2);
		m = Math.max(m, n3);
		
		System.out.println(m);
	}

} Main
import java.util.Scanner;

public class Main {
	static Scanner scan = new Scanner(System.in);
	
	public static void main(String[] args) {
		int a = scan.nextInt();
		int b = scan.nextInt();
		
		int n1 = a-b;
		int n2 = a+b;
		int n3 = a*b;
		
		int m = Math.max(n1, n2);
		m = Math.max(m, n3);
		
		System.out.println(m);
	}

}
