use std::io;
fn main() {
	let mut s = String::new();
	io::stdin().read_line(&mut s).ok();
	let n: usize = s.trim().parse().unwrap();
	let mut v = [true; 10];
	for _ in 0..n {
		let mut itr = String::new();
		io::stdin().read_line(&mut itr).ok();
		let mut itr = itr.trim().split_whitespace();
		let a: usize = itr.next().unwrap().parse().unwrap();
		let b: usize = itr.next().unwrap().parse().unwrap();
		let c: usize = itr.next().unwrap().parse().unwrap();
		let d: usize = itr.next().unwrap().parse().unwrap();
		let s: &str = itr.next().unwrap();
		
		if s == "NO" {
			v[a] = false;
			v[b] = false;
			v[c] = false;
			v[d] = false;
		} else {
			for i in 0..10 {
				if !(i == a || i == b || i == c || i == d) {
					v[i] = false;
				}
			}
		}
	}
	for i in 0..10 {
		if v[i] {
			println!("{}", i);
			break;
		}
	}
}