import strutils,strscans
var
    N = stdin.readline.parseInt
    a,b,c,d : int
    r : string
    scan : bool
    s = {0..9}
    A : set[int8]
    line : string
for i in 0..<N:
    line = stdin.readline
    scan = scanf(line,"$i $i $i $i $+\n",a,b,c,d,r)
    if r == "NO":
        s = s - {a,b,c,d}
    else:
        s = s * {a,b,c,d}

for i in s:
    echo i