#include <stdio.h>

int main(void)
{
  unsigned short n, a, yes = 0, no = 0, tmp;
  char r[3], i, j;

  scanf("%hd", &n);
  for(i = 0; i < n; i++){
    a = 0;
    for(j = 0; j < 4; j++){
      scanf("%hd", &tmp);
      a |= 1 << tmp;
    }
    scanf("%s", &r);
    if(r[0] == 'Y'){
      if(yes){
        yes &= a;
      }
      else
        yes = a;
    }
    else if(r[0] == 'N')
      no |= a;
    yes ^= yes & no;
//    printf("%hd\n", yes); 
//    printf("%hd\n", no); 
  }
  for(i = 0;; i++)
    if(yes == 1 << i ||
      !yes &&
      (no & 1 << i) != 1 << i)
      break;
  printf("%d\n", i); 
}