import java.util.Scanner;
import java.util.HashMap;
import java.util.List;
import java.util.Arrays;
import java.util.ArrayList;
import java.lang.Math;

public class Main {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int a = sc.nextInt();
        int b = sc.nextInt();
        int[] ab = {a+b, a-b, a*b};
        System.out.println(maxInt(ab));
    }

    private static int maxInt(int[] array) {
        int max = array[0];
        for (int i = 1; i < array.length; i++) {
            if (max < array[i]) max = array[i];
        }
        return max;
    }

    private static long maxLong(long[] array) {
        long max = array[0];
        for (int i = 1; i < array.length; i++) {
            if (max < array[i]) max = array[i];
        }
        return max;
    }

    private static int minInt(int[] array) {
        int min = array[0];
        for (int i = 1; i < array.length; i++) {
            if (min > array[i]) min = array[i];
        }
        return min;
    }

    private static long minLong(long[] array) {
        long min = array[0];
        for (int i = 1; i < array.length; i++) {
            if (min > array[i]) min = array[i];
        }
        return min;
    }

} import java.util.Scanner; Scanner java.util import java.util.HashMap; HashMap java.util import java.util.List; List java.util import java.util.Arrays; Arrays java.util import java.util.ArrayList; ArrayList java.util import java.lang.Math; Math java.lang public class Main {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int a = sc.nextInt();
        int b = sc.nextInt();
        int[] ab = {a+b, a-b, a*b};
        System.out.println(maxInt(ab));
    }

    private static int maxInt(int[] array) {
        int max = array[0];
        for (int i = 1; i < array.length; i++) {
            if (max < array[i]) max = array[i];
        }
        return max;
    }

    private static long maxLong(long[] array) {
        long max = array[0];
        for (int i = 1; i < array.length; i++) {
            if (max < array[i]) max = array[i];
        }
        return max;
    }

    private static int minInt(int[] array) {
        int min = array[0];
        for (int i = 1; i < array.length; i++) {
            if (min > array[i]) min = array[i];
        }
        return min;
    }

    private static long minLong(long[] array) {
        long min = array[0];
        for (int i = 1; i < array.length; i++) {
            if (min > array[i]) min = array[i];
        }
        return min;
    }

} Main public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int a = sc.nextInt();
        int b = sc.nextInt();
        int[] ab = {a+b, a-b, a*b};
        System.out.println(maxInt(ab));
    } main {
        Scanner sc = new Scanner(System.in);
        int a = sc.nextInt();
        int b = sc.nextInt();
        int[] ab = {a+b, a-b, a*b};
        System.out.println(maxInt(ab));
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int a = sc.nextInt(); a sc.nextInt() sc.nextInt sc int b = sc.nextInt(); b sc.nextInt() sc.nextInt sc int[] ab = {a+b, a-b, a*b}; ab {a+b, a-b, a*b} a+b a b a-b a b a*b a b System.out.println(maxInt(ab)) System.out.println System.out System System.out maxInt(ab) maxInt ab String[] args args private static int maxInt(int[] array) {
        int max = array[0];
        for (int i = 1; i < array.length; i++) {
            if (max < array[i]) max = array[i];
        }
        return max;
    } maxInt {
        int max = array[0];
        for (int i = 1; i < array.length; i++) {
            if (max < array[i]) max = array[i];
        }
        return max;
    } int max = array[0]; max array[0] array 0 for (int i = 1; i < array.length; i++) {
            if (max < array[i]) max = array[i];
        } int i = 1; int i = 1; i 1 i < array.length i array.length array array.length i++ i++ i {
            if (max < array[i]) max = array[i];
        } {
            if (max < array[i]) max = array[i];
        } if (max < array[i]) max = array[i]; max < array[i] max array[i] array i max = array[i] max array[i] array i return max; max int[] array array private static long maxLong(long[] array) {
        long max = array[0];
        for (int i = 1; i < array.length; i++) {
            if (max < array[i]) max = array[i];
        }
        return max;
    } maxLong {
        long max = array[0];
        for (int i = 1; i < array.length; i++) {
            if (max < array[i]) max = array[i];
        }
        return max;
    } long max = array[0]; max array[0] array 0 for (int i = 1; i < array.length; i++) {
            if (max < array[i]) max = array[i];
        } int i = 1; int i = 1; i 1 i < array.length i array.length array array.length i++ i++ i {
            if (max < array[i]) max = array[i];
        } {
            if (max < array[i]) max = array[i];
        } if (max < array[i]) max = array[i]; max < array[i] max array[i] array i max = array[i] max array[i] array i return max; max long[] array array private static int minInt(int[] array) {
        int min = array[0];
        for (int i = 1; i < array.length; i++) {
            if (min > array[i]) min = array[i];
        }
        return min;
    } minInt {
        int min = array[0];
        for (int i = 1; i < array.length; i++) {
            if (min > array[i]) min = array[i];
        }
        return min;
    } int min = array[0]; min array[0] array 0 for (int i = 1; i < array.length; i++) {
            if (min > array[i]) min = array[i];
        } int i = 1; int i = 1; i 1 i < array.length i array.length array array.length i++ i++ i {
            if (min > array[i]) min = array[i];
        } {
            if (min > array[i]) min = array[i];
        } if (min > array[i]) min = array[i]; min > array[i] min array[i] array i min = array[i] min array[i] array i return min; min int[] array array private static long minLong(long[] array) {
        long min = array[0];
        for (int i = 1; i < array.length; i++) {
            if (min > array[i]) min = array[i];
        }
        return min;
    } minLong {
        long min = array[0];
        for (int i = 1; i < array.length; i++) {
            if (min > array[i]) min = array[i];
        }
        return min;
    } long min = array[0]; min array[0] array 0 for (int i = 1; i < array.length; i++) {
            if (min > array[i]) min = array[i];
        } int i = 1; int i = 1; i 1 i < array.length i array.length array array.length i++ i++ i {
            if (min > array[i]) min = array[i];
        } {
            if (min > array[i]) min = array[i];
        } if (min > array[i]) min = array[i]; min > array[i] min array[i] array i min = array[i] min array[i] array i return min; min long[] array array public class Main {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int a = sc.nextInt();
        int b = sc.nextInt();
        int[] ab = {a+b, a-b, a*b};
        System.out.println(maxInt(ab));
    }

    private static int maxInt(int[] array) {
        int max = array[0];
        for (int i = 1; i < array.length; i++) {
            if (max < array[i]) max = array[i];
        }
        return max;
    }

    private static long maxLong(long[] array) {
        long max = array[0];
        for (int i = 1; i < array.length; i++) {
            if (max < array[i]) max = array[i];
        }
        return max;
    }

    private static int minInt(int[] array) {
        int min = array[0];
        for (int i = 1; i < array.length; i++) {
            if (min > array[i]) min = array[i];
        }
        return min;
    }

    private static long minLong(long[] array) {
        long min = array[0];
        for (int i = 1; i < array.length; i++) {
            if (min > array[i]) min = array[i];
        }
        return min;
    }

} public class Main {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int a = sc.nextInt();
        int b = sc.nextInt();
        int[] ab = {a+b, a-b, a*b};
        System.out.println(maxInt(ab));
    }

    private static int maxInt(int[] array) {
        int max = array[0];
        for (int i = 1; i < array.length; i++) {
            if (max < array[i]) max = array[i];
        }
        return max;
    }

    private static long maxLong(long[] array) {
        long max = array[0];
        for (int i = 1; i < array.length; i++) {
            if (max < array[i]) max = array[i];
        }
        return max;
    }

    private static int minInt(int[] array) {
        int min = array[0];
        for (int i = 1; i < array.length; i++) {
            if (min > array[i]) min = array[i];
        }
        return min;
    }

    private static long minLong(long[] array) {
        long min = array[0];
        for (int i = 1; i < array.length; i++) {
            if (min > array[i]) min = array[i];
        }
        return min;
    }

} Main
import java.util.Scanner;
import java.util.HashMap;
import java.util.List;
import java.util.Arrays;
import java.util.ArrayList;
import java.lang.Math;

public class Main {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int a = sc.nextInt();
        int b = sc.nextInt();
        int[] ab = {a+b, a-b, a*b};
        System.out.println(maxInt(ab));
    }

    private static int maxInt(int[] array) {
        int max = array[0];
        for (int i = 1; i < array.length; i++) {
            if (max < array[i]) max = array[i];
        }
        return max;
    }

    private static long maxLong(long[] array) {
        long max = array[0];
        for (int i = 1; i < array.length; i++) {
            if (max < array[i]) max = array[i];
        }
        return max;
    }

    private static int minInt(int[] array) {
        int min = array[0];
        for (int i = 1; i < array.length; i++) {
            if (min > array[i]) min = array[i];
        }
        return min;
    }

    private static long minLong(long[] array) {
        long min = array[0];
        for (int i = 1; i < array.length; i++) {
            if (min > array[i]) min = array[i];
        }
        return min;
    }

}
