# input
s = input()

win_east = s.find('OOO')
win_west = s.find('XXX')

# process

if win_east != -1 or win_west != -1:
    if win_west == -1:
        print('East')
    elif win_east == -1:
        print('West')
    else:
        if win_west < win_east:
            print('West')
        else:
            print('East')
            
elif (win_east != -1 and win_west != -1) or (win_east == -1 and win_west == -1):
        print('NA')