import java.util.Arrays;
import java.util.Scanner;

// https://atcoder.jp/contests/abc137/tasks/abc137_a
public class Main {

	public static void main(String[] args) {
		// TODO 自動生成されたメソッド・スタブ
		Scanner sc = new Scanner(System.in);
		int A = sc.nextInt();
		int B = sc.nextInt();
		sc.close();


		int[] max = new int[3];
		//Integer[] max = new Integer[3];
		max[0] = A * B;
		max[1] = A - B;
		max[2] = A + B;

		Arrays.sort(max);
		System.out.println(max[2]);
	}

}

/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz