import java.util.Arrays;
import java.util.Scanner;

public class Test {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		int n = sc.nextInt(), a,b,c,d, s;
		boolean[] bo = new boolean[10];
		Arrays.fill(bo, true);
		for(int i = 0; i < n; i++){
			a = sc.nextInt();
			b = sc.nextInt();
			c = sc.nextInt();
			d = sc.nextInt();
			s = sc.next().length();
			if(s == 2){
				bo[a] = false;
				bo[b] = false;
				bo[c] = false;
				bo[d] = false;
			} else {
				for(int j = 0; j < 10; j++){
					if(a != j && b != j && c != j && d != j){
						bo[j] = false;
					}
				}
			}
		}
		for(int j = 0; j < 10; j++){
			if(bo[j]){
				System.out.println(j);
				return;
			}
		}
	}
}