str=[] a=raw_input().split(" ") num1=int(a[0]) num=int(a[1]) abc=["A","B","C","D","E","F","G","H"] for i in range(num1): s=raw_input() str.append(s) if len(s)==1: abc.remove(s) snum=[] snum.append(0) def f(n,str1): str1+=n for i in range(num1): if str1.find(str[i])!=-1: return if len(str1)==num: snum[0]+=1 return for zi in abc: f(zi,str1) f("","") print snum[0]%100007