S = input()
N = len(S)

flag = "NA"
for i in range(N):
    if S[i] == "O":
        if i+1 < N and i+2 < N:
            if S[i+1] == "O" and S[i+2] == "O":
                flag = "East"
                break
    if S[i] == "X":
        if i+1 < N and i+2 < N:
            if S[i+1] == "X" and S[i+2] == "X":
                flag = "West"
                break

print(flag)