20250320

import sys

sys.setrecursionlimit(10000)

def dfs(c):

global n,k,a,d,ans,g

if c==k:

t=1

e=''.join(map(str,d))

for i in range(len(f)):

if f[i]==e:

t=0

break

if t==1:

ans=ans+1

f.append(e)

for i in range(n):

if not g[i]==1:

d.append(a[i])

g[i]=1

dfs(c+1)

d.pop()

g[i]=0

a=[]

d=[]

f=[]

ans=int(0)

n=int(input())

k=int(input())

g=[0 for i in range(n)]

for i in range(n):

b=int(input())

a.append(b)

dfs(0)

print(ans)