// 2019/05/14
// AtCoder Beginner Contest 053 - A
// (stdin: type Ctrl + D after input)
 
"use strict";
 
function Main(in_input){
    // Modify Input
    var in_lines = in_input.split("\n");
    var in_line1 = in_lines[0].split(" ");
    var x = parseInt(in_line1[0], 10);
 
    var ans = "";
    // Judge
    if(x < 1200){
        ans = "ABC";
    } else {
        ans = "ARC";
    }
 
    // Output
    console.log(ans);
}
 
Main(require("fs").readFileSync("/dev/stdin", "utf8"));