#python 3.5.2

S = input()
x, o = [0, 0]
for Si in S:
    if Si == 'X':
        x += 1
        o = 0
    if Si == 'O':
        x = 0
        o += 1
    if x == 3:
        print('West')
        break
    if o == 3:
        print('East')
        break

if not (x == 3 or o == 3):
    print('NA')