#include <stdio.h>
#include <string.h>

int main() {
    int i, j, k, l = 0, lsize, N, A[6][4], B[100], cnt = 0, ANS[10] = {0,1,2,3,4,5,6,7,8,9};
    char s[6][10];

    scanf("%d", &N);
    for (i = 0; i < N; i++) {
        scanf("%d %d %d %d", &A[i][0], &A[i][1], &A[i][2], &A[i][3]);
        scanf("%s", s[i]);
    }


    for (i = 0; i < N ; i++) {
        for (j = 0; j < 4; j++) {
            if (strcmp(s[i], "NO") == 0) {
                ANS[A[i][j]] = -1;
            }
            else {
                B[l++] = A[i][j];
            }
        }
    }
    
    for( k = 0; k <10; k++){
        if (ANS[k] != -1) {
            cnt++;
        }
    }
    if (cnt == 1) {
        printf("%d\n", ANS[k-1]);
        return 0;
    }

    lsize = l ;
    l = 0;
    for (i = 0; i < N; i++) {
        if (strcmp(s[i], "YES") == 0) {
            for (k = 0; k < lsize; k++) {
                for (l = k + 1; l < lsize; l++) {
                    if (B[k] == B[l] && ANS[B[l]] != -1) {
                        printf("%d\n", B[l]);
                        return 0;
                    }
                }
            }
        }
    }
}