import java.util.*;

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

    String[] nums = new String[10];
    for (int i = 0; i < 10; i++) {
      nums[i] = "none";
    }

    int s = sc.nextInt();

    for (int i = 0; i < s; i++) {
      int[] ansNums = new int[4];
      for (int j = 0; j < 4; j++) {
        ansNums[j] = sc.nextInt();
      }
      String ans = sc.next();
      Arrays.sort(ansNums);
      if (ans.equals("NO")) {
        for (int index : ansNums) {
          nums[index] = "false";
        }
      } else {
        for (int j = 0; j < 10; j++) {
          if (Arrays.binarySearch(ansNums, j) < 0) {
            nums[j] = "false";
          } else {
            if (!nums[j].equals("false")) {
              nums[j] = "true";
            }
          }
        }
      }
    }
    int ans = 0;
    int trueIndex = Arrays.binarySearch(nums, "true");
    int noneIndex = Arrays.binarySearch(nums, "none");;
    if (trueIndex < 0) {
      ans = noneIndex;
    } else {
      ans = trueIndex;
    }
    System.out.println(ans);
  }
}