题解 | #牛牛的等差数列#

import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; public class Main{ public static void main(String[] args) throws IOException{ BufferedReader bf = new BufferedReader(new InputStreamReader(System.in)); String str[] = bf.readLine().split(" "); int a = Integer.parseInt(str[0]); int b = Integer.parseInt(str[1]); int x = b-a; int c = b+x; System.out.println(c); } }