def is_impossible(flag):
    if flag:
        print(-1)
        exit()


W, H, X = map(int, input().split())
is_impossible(X > 36)
is_impossible(W % 3 != 2 or W % 3 != 2)
M = [[0] * W for _ in range(H)]
for i in range(0, H, 3):
    for j in range(0, W, 3):
        M[i][j] = X//4
        M[i][j+1] = (X+1)//4
        M[i+1][j] = (X+2)//4
        M[i+1][j+1] = (X+3)//4
for m in M:
    print(''.join(map(str, m)))