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

void YES(int gue[], int *ans);
void NO(int gue[], int *ans);
void clean(int *ans);


int main(void) {
    int N;
    int A_D[4] = {0};
    int Ans[10];
    int *pAns = Ans;
    char R[5];
    char *pR;
    int seikai;
    scanf("%d", &N);
    for (int i = 0; i < 10; i++) {
        Ans[i] = i;
    }

    for (int i = 0; i < N; i++) {
        for (int j = 0; j < 4; j++) {
            scanf("%d", &A_D[j]);
        }
        scanf("%s", R);

        if (R == "YES") {
            YES(A_D, pAns);
        } else {
            NO(A_D, pAns);
        }
    }
    for (int i = 0; i < 10; i++) {
        if (Ans[i] != 10) {
            seikai = Ans[i];
            break;
        }
    }
    printf("%d", seikai);

    return EXIT_SUCCESS;
}

void YES(int gue[], int *ans) {
    for (int i = 0; i < 10; i++) {
        for (int j = 0; j < 4; j++) {
            if (*(ans+i) == 10) {
                continue;
            } else if (*(ans+i) != gue[j]) {
                *(ans+i) = 10;
            }
        }
    }
    return;
}

void NO(int gue[], int *ans) {
    for (int i = 0; i < 10; i++) {
        for (int j = 0; j < 4; j++) {
            if (*(ans+i) == 10) {
                continue;
            } else if (*(ans+i) == gue[j]) {
                *(ans+i) = 10;
            }
        }
    }
    return;
}