102171: [AtCoder]ABC217 B - AtCoder Quiz

Problem Statement

AtCoder currently holds four series of regular contests: ABC, ARC, AGC, and AHC.

What is the series of regular contests currently held by AtCoder in addition to $S_1$, $S_2$, and $S_3$?

Constraints

• Each of $S_1$, $S_2$, and $S_3$ is ABC, ARC, AGC, or AHC.
• $S_1$, $S_2$, and $S_3$ are pairwise different.

Input

Input is given from Standard Input in the following format:

$S_1$
$S_2$
$S_3$

Output

Print the answer.

Sample Input 1

ARC
AGC
AHC

Sample Output 1

ABC

Given in input are ARC, AGC, and AHC. The rest is ABC.

Sample Input 2

AGC
ABC
ARC

Sample Output 2

AHC

问题描述

AtCoder 目前举办了四个系列的常规比赛：ABC、ARC、AGC和AHC。

除了$S_1$、$S_2$和$S_3$之外，AtCoder 目前还举办了哪些系列的常规比赛？

限制条件

• $S_1$、$S_2$和$S_3$分别代表ABC、ARC、AGC或AHC。
• $S_1$、$S_2$和$S_3$两两不同。

输入

从标准输入以以下格式获取输入：

$S_1$
$S_2$
$S_3$

输出

打印答案。

样例输入 1

ARC
AGC
AHC

样例输出 1

ABC

输入给出的是ARC、AGC和AHC。剩下的就是ABC。

样例输入 2

AGC
ABC
ARC

样例输出 2

AHC