num = '0123456789'
for i in range(int(input())):
    dat = input().split()
    tmp = '0123456789'
    if(dat[-1] == 'YES'):
        for j in range(4):
            tmp = tmp.replace(str(dat[j]),'')
        for k in range(len(tmp)):
            num = num.replace(str(tmp[k]),'')
    else:
        for j in range(4):
            num = num.replace(str(dat[j]),'')
print(num)