import java.io.*;
import java.util.*;

public class Main {
	
	public static void main(String[] args) {
		FastReader scan = new FastReader();
		PrintWriter out = new PrintWriter(System.out);
		Task solver = new Task();
		solver.solve(1, scan, out);
		out.close();
	}
	
	static class Task {
		public void solve(int testNumber, FastReader scan, PrintWriter out) {
			int a = scan.nextInt(), b = scan.nextInt();
			out.println(Math.max(Math.max(a+b, a*b), a-b));
		}
	}
	
	

	static class FastReader {
		BufferedReader br;
		StringTokenizer st;

		public FastReader() {
			br = new BufferedReader(new InputStreamReader(System.in));
		}
		public FastReader(String s) throws FileNotFoundException {
			br = new BufferedReader(new FileReader(new File(s)));
		}

		String next() {
			while (st == null || !st.hasMoreElements()) {
				try {
					st = new StringTokenizer(br.readLine());
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			return st.nextToken();
		}

		int nextInt() {
			return Integer.parseInt(next());
		}

		long nextLong() {
			return Long.parseLong(next());
		}

		double nextDouble() {
			return Double.parseDouble(next());
		}

		String nextLine() {
			String str = "";
			try {
				str = br.readLine();
			} catch (IOException e) {
				e.printStackTrace();
			}
			return str;
		}
	}

} import java.io.*; io.* java import java.util.*; util.* java public class Main {
	
	public static void main(String[] args) {
		FastReader scan = new FastReader();
		PrintWriter out = new PrintWriter(System.out);
		Task solver = new Task();
		solver.solve(1, scan, out);
		out.close();
	}
	
	static class Task {
		public void solve(int testNumber, FastReader scan, PrintWriter out) {
			int a = scan.nextInt(), b = scan.nextInt();
			out.println(Math.max(Math.max(a+b, a*b), a-b));
		}
	}
	
	

	static class FastReader {
		BufferedReader br;
		StringTokenizer st;

		public FastReader() {
			br = new BufferedReader(new InputStreamReader(System.in));
		}
		public FastReader(String s) throws FileNotFoundException {
			br = new BufferedReader(new FileReader(new File(s)));
		}

		String next() {
			while (st == null || !st.hasMoreElements()) {
				try {
					st = new StringTokenizer(br.readLine());
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			return st.nextToken();
		}

		int nextInt() {
			return Integer.parseInt(next());
		}

		long nextLong() {
			return Long.parseLong(next());
		}

		double nextDouble() {
			return Double.parseDouble(next());
		}

		String nextLine() {
			String str = "";
			try {
				str = br.readLine();
			} catch (IOException e) {
				e.printStackTrace();
			}
			return str;
		}
	}

} Main public static void main(String[] args) {
		FastReader scan = new FastReader();
		PrintWriter out = new PrintWriter(System.out);
		Task solver = new Task();
		solver.solve(1, scan, out);
		out.close();
	} main {
		FastReader scan = new FastReader();
		PrintWriter out = new PrintWriter(System.out);
		Task solver = new Task();
		solver.solve(1, scan, out);
		out.close();
	} FastReader scan = new FastReader(); scan new FastReader() PrintWriter out = new PrintWriter(System.out); out new PrintWriter(System.out) Task solver = new Task(); solver new Task() solver.solve(1, scan, out) solver.solve solver 1 scan out out.close() out.close out String[] args args static class Task {
		public void solve(int testNumber, FastReader scan, PrintWriter out) {
			int a = scan.nextInt(), b = scan.nextInt();
			out.println(Math.max(Math.max(a+b, a*b), a-b));
		}
	} Task public void solve(int testNumber, FastReader scan, PrintWriter out) {
			int a = scan.nextInt(), b = scan.nextInt();
			out.println(Math.max(Math.max(a+b, a*b), a-b));
		} solve {
			int a = scan.nextInt(), b = scan.nextInt();
			out.println(Math.max(Math.max(a+b, a*b), a-b));
		} int a = scan.nextInt() a scan.nextInt() scan.nextInt scan b = scan.nextInt(); b scan.nextInt() scan.nextInt scan out.println(Math.max(Math.max(a+b, a*b), a-b)) out.println out 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 int testNumber testNumber FastReader scan scan PrintWriter out out static class FastReader {
		BufferedReader br;
		StringTokenizer st;

		public FastReader() {
			br = new BufferedReader(new InputStreamReader(System.in));
		}
		public FastReader(String s) throws FileNotFoundException {
			br = new BufferedReader(new FileReader(new File(s)));
		}

		String next() {
			while (st == null || !st.hasMoreElements()) {
				try {
					st = new StringTokenizer(br.readLine());
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			return st.nextToken();
		}

		int nextInt() {
			return Integer.parseInt(next());
		}

		long nextLong() {
			return Long.parseLong(next());
		}

		double nextDouble() {
			return Double.parseDouble(next());
		}

		String nextLine() {
			String str = "";
			try {
				str = br.readLine();
			} catch (IOException e) {
				e.printStackTrace();
			}
			return str;
		}
	} FastReader BufferedReader br; br StringTokenizer st; st public FastReader() {
			br = new BufferedReader(new InputStreamReader(System.in));
		} FastReader {
			br = new BufferedReader(new InputStreamReader(System.in));
		} br = new BufferedReader(new InputStreamReader(System.in)) br new BufferedReader(new InputStreamReader(System.in)) public FastReader(String s) throws FileNotFoundException {
			br = new BufferedReader(new FileReader(new File(s)));
		} FastReader {
			br = new BufferedReader(new FileReader(new File(s)));
		} br = new BufferedReader(new FileReader(new File(s))) br new BufferedReader(new FileReader(new File(s))) String s s String next() {
			while (st == null || !st.hasMoreElements()) {
				try {
					st = new StringTokenizer(br.readLine());
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			return st.nextToken();
		} next {
			while (st == null || !st.hasMoreElements()) {
				try {
					st = new StringTokenizer(br.readLine());
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			return st.nextToken();
		} while (st == null || !st.hasMoreElements()) {
				try {
					st = new StringTokenizer(br.readLine());
				} catch (IOException e) {
					e.printStackTrace();
				}
			} st == null || !st.hasMoreElements() st == null st null !st.hasMoreElements() st.hasMoreElements() st.hasMoreElements st {
				try {
					st = new StringTokenizer(br.readLine());
				} catch (IOException e) {
					e.printStackTrace();
				}
			} try {
					st = new StringTokenizer(br.readLine());
				} catch (IOException e) {
					e.printStackTrace();
				} catch (IOException e) {
					e.printStackTrace();
				} IOException e {
					e.printStackTrace();
				} e.printStackTrace() e.printStackTrace e {
					st = new StringTokenizer(br.readLine());
				} st = new StringTokenizer(br.readLine()) st new StringTokenizer(br.readLine()) return st.nextToken(); st.nextToken() st.nextToken st int nextInt() {
			return Integer.parseInt(next());
		} nextInt {
			return Integer.parseInt(next());
		} return Integer.parseInt(next()); Integer.parseInt(next()) Integer.parseInt Integer next() next long nextLong() {
			return Long.parseLong(next());
		} nextLong {
			return Long.parseLong(next());
		} return Long.parseLong(next()); Long.parseLong(next()) Long.parseLong Long next() next double nextDouble() {
			return Double.parseDouble(next());
		} nextDouble {
			return Double.parseDouble(next());
		} return Double.parseDouble(next()); Double.parseDouble(next()) Double.parseDouble Double next() next String nextLine() {
			String str = "";
			try {
				str = br.readLine();
			} catch (IOException e) {
				e.printStackTrace();
			}
			return str;
		} nextLine {
			String str = "";
			try {
				str = br.readLine();
			} catch (IOException e) {
				e.printStackTrace();
			}
			return str;
		} String str = ""; str "" try {
				str = br.readLine();
			} catch (IOException e) {
				e.printStackTrace();
			} catch (IOException e) {
				e.printStackTrace();
			} IOException e {
				e.printStackTrace();
			} e.printStackTrace() e.printStackTrace e {
				str = br.readLine();
			} str = br.readLine() str br.readLine() br.readLine br return str; str public class Main {
	
	public static void main(String[] args) {
		FastReader scan = new FastReader();
		PrintWriter out = new PrintWriter(System.out);
		Task solver = new Task();
		solver.solve(1, scan, out);
		out.close();
	}
	
	static class Task {
		public void solve(int testNumber, FastReader scan, PrintWriter out) {
			int a = scan.nextInt(), b = scan.nextInt();
			out.println(Math.max(Math.max(a+b, a*b), a-b));
		}
	}
	
	

	static class FastReader {
		BufferedReader br;
		StringTokenizer st;

		public FastReader() {
			br = new BufferedReader(new InputStreamReader(System.in));
		}
		public FastReader(String s) throws FileNotFoundException {
			br = new BufferedReader(new FileReader(new File(s)));
		}

		String next() {
			while (st == null || !st.hasMoreElements()) {
				try {
					st = new StringTokenizer(br.readLine());
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			return st.nextToken();
		}

		int nextInt() {
			return Integer.parseInt(next());
		}

		long nextLong() {
			return Long.parseLong(next());
		}

		double nextDouble() {
			return Double.parseDouble(next());
		}

		String nextLine() {
			String str = "";
			try {
				str = br.readLine();
			} catch (IOException e) {
				e.printStackTrace();
			}
			return str;
		}
	}

} public class Main {
	
	public static void main(String[] args) {
		FastReader scan = new FastReader();
		PrintWriter out = new PrintWriter(System.out);
		Task solver = new Task();
		solver.solve(1, scan, out);
		out.close();
	}
	
	static class Task {
		public void solve(int testNumber, FastReader scan, PrintWriter out) {
			int a = scan.nextInt(), b = scan.nextInt();
			out.println(Math.max(Math.max(a+b, a*b), a-b));
		}
	}
	
	

	static class FastReader {
		BufferedReader br;
		StringTokenizer st;

		public FastReader() {
			br = new BufferedReader(new InputStreamReader(System.in));
		}
		public FastReader(String s) throws FileNotFoundException {
			br = new BufferedReader(new FileReader(new File(s)));
		}

		String next() {
			while (st == null || !st.hasMoreElements()) {
				try {
					st = new StringTokenizer(br.readLine());
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			return st.nextToken();
		}

		int nextInt() {
			return Integer.parseInt(next());
		}

		long nextLong() {
			return Long.parseLong(next());
		}

		double nextDouble() {
			return Double.parseDouble(next());
		}

		String nextLine() {
			String str = "";
			try {
				str = br.readLine();
			} catch (IOException e) {
				e.printStackTrace();
			}
			return str;
		}
	}

} Main
import java.io.*;
import java.util.*;

public class Main {
	
	public static void main(String[] args) {
		FastReader scan = new FastReader();
		PrintWriter out = new PrintWriter(System.out);
		Task solver = new Task();
		solver.solve(1, scan, out);
		out.close();
	}
	
	static class Task {
		public void solve(int testNumber, FastReader scan, PrintWriter out) {
			int a = scan.nextInt(), b = scan.nextInt();
			out.println(Math.max(Math.max(a+b, a*b), a-b));
		}
	}
	
	

	static class FastReader {
		BufferedReader br;
		StringTokenizer st;

		public FastReader() {
			br = new BufferedReader(new InputStreamReader(System.in));
		}
		public FastReader(String s) throws FileNotFoundException {
			br = new BufferedReader(new FileReader(new File(s)));
		}

		String next() {
			while (st == null || !st.hasMoreElements()) {
				try {
					st = new StringTokenizer(br.readLine());
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			return st.nextToken();
		}

		int nextInt() {
			return Integer.parseInt(next());
		}

		long nextLong() {
			return Long.parseLong(next());
		}

		double nextDouble() {
			return Double.parseDouble(next());
		}

		String nextLine() {
			String str = "";
			try {
				str = br.readLine();
			} catch (IOException e) {
				e.printStackTrace();
			}
			return str;
		}
	}

}
