N,K=map(int,input().split())
S=[list(input()) for _ in range(N)]

def go(arr):
    ret = 0
    for i in range(K-1,-1,-1):
        ret = ret * 5 + int(arr[i])
    return ret
def goinv(m):
    ret = [0]*K
    for i in range(K):
        ret[i] = m%5
        m//=5
    return ret

M = 5**K
A=[0]*M
for i in range(N):
    idx = go(S[i])
    A[idx] += 1
for k in range(K):
    for m in range(M-1,-1,-1):
        arr = goinv(m)
        if (arr[k] != 4):
            arr[k] += 1
            nm = go(arr)
            A[m] += A[nm]

ans = 0
for i in range(N):
    idx = go(S[i])
    if A[idx] > 1: ans += 1
print(ans)