//
//  main.swift
//  AtCoder
//
//  Created by Taketo Yoshida on 17/3/20.
//  Copyright © 2020 Taketo Yoshida. All rights reserved.
//

#if os(Linux)
    import Glibc
#else
    import Foundation
    import Darwin
#endif

#if swift(<3.0)
extension String: CollectionType {}
#endif

func readInts() -> [Int] {
    return readLine()!.split(separator: " ").map { Int($0)! }
}

prefix operator *
prefix func * <T> (a: [T]) -> (T, T) { return (a[0], a[1]) }
prefix func * <T> (a: [T]) -> (T, T, T) { return (a[0], a[1], a[2]) }

let (A, B) = *readInts()

print(max(A + B, A - B, A * B))
