N, K = map(int, input().split())

tuples = []
for _ in range(N):
    s = input().strip()
    tuples.append([int(c) for c in s])

mask_per_dim = [[0] * 5 for _ in range(K)]

for i in range(N):
    s_list = tuples[i]
    for j in range(K):
        s = s_list[j]
        for v in range(s + 1):
            mask_per_dim[j][v] |= 1 << i

count = 0
for i in range(N):
    s_list = tuples[i]
    masks = [mask_per_dim[j][s_list[j]] for j in range(K)]
    combined = masks[0]
    for j in range(1, K):
        combined &= masks[j]
    if combined != (1 << i):
        count += 1

print(count)