W, H, C = input().split(' ')

K = 'WB'
A = 'BW'
S = int(W) // 2


if int(W) % 2 == 1:
    S_K = K * S + 'W'
    S_A = A * S + 'B'
else:
    S_K = K * S 
    S_A = A * S





for i in range(int(H)):
    if i % 2 == 0 and C == 'B':
        I = S_A
        print(I)
        C = 'W'
    elif i % 2 == 0 and C == 'W':
        I = S_K
        print(I)
        C = 'B'
    elif i % 2 == 1 and C == 'W':
        I = S_K
        print(I)
        C = 'B'
    elif i % 2 == 1 and C == 'B':
        I = S_A 
        print(I)
        C = 'W'