题解 | #(a+b-c)*d的计算问题#

import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int a = scan.nextInt();
        int b = scan.nextInt();
        int c = scan.nextInt();
        int d = scan.nextInt();
        System.out.println((a + b - c) * d);
    }
}