S=list(input())

n=len(S)


if(n<3):
   print('NA')

else:
    for i in range(n-2):
        if( S[i]=='O' and S[i+1]=='O' and S[i+2]=='O'):
           print('East')
           break
        elif(S[i]=='X' and S[i+1]=='X' and S[i+2]=='X'):
           print('West')
           break
        elif(i==n-3):
           print('NA')