s = input()

e = "OOO"
w = "XXX"

NO_STRAIGHT_WIN = 1000


def f(word, pat):
    win = word.find(pat)
    if win == -1:
        win = NO_STRAIGHT_WIN

    return win


win_e = f(s, e)
win_w = f(s, w)

if win_e == NO_STRAIGHT_WIN and win_w == NO_STRAIGHT_WIN:
    ans = "NA"
elif win_e < win_w:
    ans = "East"
else:
    ans = "West"

print(ans)