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<bits/stdc++.h>

using namespace std;
int main(){
    long long int N, QQ[200001], temp, counter=0;
    // int qq1[200001], qq2[200001];
    cin>>N;
    
    for(long long int i=1; i<=N; i++){
        cin>>QQ[i]; 
    }
    for(long long int i=1;i<=N;i++){
        for(long long int j=i+1;j<=N;j++){
            // if(qq[i][j]!=1 && qq[j][i]!=1){
                // qq[i][j] = 1;
                // qq[j][i] = 1;
                if(QQ[i]+QQ[j] == abs(i-j)){
                    counter++;
                }
            // }
            
        }
    }

    cout<<counter<<"\n";

    return 0;
}