Problem:
Score : 100 points

Problem Statement

AtCoder Inc. holds a contest every Saturday.

There are two types of contests called ABC and ARC, and just one of them is held at a time.

The company holds these two types of contests alternately: an ARC follows an ABC and vice versa.

Given a string S representing the type of the contest held last week, print the string representing the type of the contest held this week.

Constraints

S is ABC or ARC.

Input

Input is given from Standard Input in the following format:

S

Output

Print the string representing the type of the contest held this week.

Sample Input 1

ABC

Sample Output 1

ARC

They held an ABC last week, so they will hold an ARC this week.

Solution in C (GCC 9.2.1) (judge verdict: Accepted)

#include<stdio.h>
#include <stdlib.h>


//クイックソート用　昇順
int compare_int(const void *a, const void *b)
{
    return *(int*)a - *(int*)b;
}
//qsort(配列の先頭ポインタ, データ数, 1データのサイズ, compare_int);


int main()
{
    int s[3];
    scanf("%s",s);
  if((strcmp(s, "ABC\0") == 0) )
  {
    printf("ARC");
  }
  else
  {
      printf("ABC");
  }
    return 0;
}