w,h,c = input().split()
x = ["W","B"]
a = 0
if c == x[0]:
    a = 1
else:
    a = 0
for i in range(int(h)):
    a += 1
    a %= 2
    if a == 0:
        b = 1
    else:
        b = 0
    z = []
    for j in range(int(w)):
        b += 1
        b %= 2
        z.append(x[b])
    print(*z,sep="")