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: Wrong Answer)

#include<stdio.h>
int main()
{
    char A[4];
    gets(A);
    int i,len,k=0,p=0;
    len=strlen(A);
    for(i=0;i<len;i++)
    {
        if(A[i]=='A'||A[i]=='B' || A[i]=='C')
        {
            k++;
        }
        else if(A[i]=='A'||A[i]=='R' || A[i]=='C')
        {
            p++;
        }
    }
    if(k==len) printf("ARC\n");
    else if(p==len) printf("ARC\n");
}