"""

"""

import sys
from sys import stdin

def encode(lis):
    now = 0
    for j in range(K):
        now *= 5
        now += int(lis[j])
    return now

N,K = map(int,stdin.readline().split())

S = [ list(stdin.readline()[:-1]) for i in range(N) ]

dp = [0] * (5**K)

for i in range(N):

    now = 0
    for j in range(K):
        now *= 5
        now += int(S[i][j])

    dp[now] += 1

for i in range(len(dp)-1,-1,-1):

    dec = []
    itmp = i
    for j in range(K):
        dec.append(itmp % 5)
        itmp //= 5
    dec.reverse()

    #print (i,dec,"qopqowq")

    for j in range(K):
        dec[j] -= 1
        if dec[j] >= 0:
            enc = encode(dec)
            #print (i,dec,enc)
            dp[enc] += dp[i]
        dec[j] += 1



ans = 0    
for i in range(N):

    now = 0
    for j in range(K):
        now *= 5
        now += int(S[i][j])

    if dp[now] > 1:
        ans += 1

#print (dp)
print (ans)