fn main() {
    input!{
        n: usize,
        abcdr: [([usize; 4], String); n],
    }
    let mut candi = vec![vec![false; 10]; n];
    for (i, (abcd, r)) in abcdr.iter().enumerate() {
        if r == "YES" {
            for &s in abcd {
                candi[i][s] = true;
            }
        } else {
            for j in 0..10 {
                candi[i][j] = true;
            }
            for &s in abcd {
                candi[i][s] = false;
            }
        }
    }
    for j in 0..10 {
        let mut ok = true;
        for i in 0..n {
            ok &= candi[i][j];
        }
        if ok {
            println!("{}", j);
            return;
        }
    }
    println!("0");
}

#[macro_export]
macro_rules! input {
    (source = $s:expr, $($r:tt)*) => {
        let mut iter = $s.split_whitespace();
        input_inner!{iter, $($r)*}
    };
    ($($r:tt)*) => {
        #[allow(unused_mut)]
        let mut s = {
            use std::io::Read;
            let mut s = String::new();
            std::io::stdin().read_to_string(&mut s).unwrap();
            s
        };
        let mut iter = s.split_whitespace();
        input_inner!{iter, $($r)*}
    };
}

#[macro_export]
macro_rules! input_inner {
    ($iter:expr) => {};
    ($iter:expr, ) => {};

    ($iter:expr, $var:ident : $t:tt $($r:tt)*) => {
        let $var = read_value!($iter, $t);
        input_inner!{$iter $($r)*}
    };
}

#[macro_export]
macro_rules! read_value {
    ($iter:expr, ( $($t:tt),* )) => {
        ( $(read_value!($iter, $t)),* )
    };

    ($iter:expr, [ $t:tt ; $len:expr ]) => {
        (0..$len).map(|_| read_value!($iter, $t)).collect::<Vec<_>>()
    };

    ($iter:expr, chars) => {
        read_value!($iter, String).chars().collect::<Vec<char>>()
    };

    ($iter:expr, usize1) => {
        read_value!($iter, usize) - 1
    };

    ($iter:expr, $t:ty) => {
        $iter.next().unwrap().parse::<$t>().expect("Parse error")
    };
}