#include <bits/stdc++.h>
using namespace std;

using LL = long long;

int main()
{
    cin.tie(0);
    ios::sync_with_stdio(false);

    LL x;
    cin >> x;

    if(x<1200){
        cout << "ABC" << endl;
    }else{
        cout << "ARC" << endl;
    }

    return 0;
}