S = input()
if S.count("OOO") == 0 and S.count("XXX") == 0:
    print("NA")
elif S.count("OOO") == 0:
    print("West")
elif S.count("XXX") == 0:
    print("East")
else:
    if S.index("OOO") < S.index("XXX"):
        print("East")
    else:
        print("West")