//Beiba.cpp rulit!
#include <bits/stdc++.h>
using namespace std;
#define open freopen ("sum.in","r",stdin), freopen ("sum.out","w",stdout);
#define nl '\n'
#define ll long long int
#define pb push_back
#define sz size()
#define all(x) x.begin(), x.end()
#define S second
#define F first
#define co continue
#define NO cout<<"NO"<<nl
#define YES cout<<"YES"<<nl
#define No cout<<"No"<<nl
#define Yes cout<<"Yes"<<nl
#define rt return
#define str string
#define pot fixed<<setprecision
#define int ll
#define pi pair<int,int>
#define vi vector
#define MAI INT64_MAX
#define MII INT64_MIN
const int inf=1e18, mod=1e9+7, N=3e5+7;
int n,d,ans;
str a[N];
map <str,int> cnt;
void dr1(int idx){
str s=a[idx];
for(int pos=0; pos<4; pos++){
for(char buk='0'; buk<='9'; buk++){
s[pos]=buk;
if(s==a[idx]) co;
ans+=cnt[s];
}
for(char buk='a'; buk<='z'; buk++){
s[pos]=buk;
if(s==a[idx]) co;
ans+=cnt[s];
}
s=a[idx];
}
}
int dr2(int idx){
str s=a[idx];
int res=0;
for(int pos=0; pos<4; pos++){
for(char buk='0'; buk<='9'; buk++){
s[pos]=buk;
if(buk==a[idx][pos]) co;
for(int pos2=0; pos2<4; pos2++){
if(pos==pos2) co;
for(char buk2='0'; buk2<='9'; buk2++){
s[pos2]=buk2;
if(buk2==a[idx][pos2]) co;
res+=cnt[s];
}
for(char buk2='a'; buk2<='z'; buk2++){
s[pos2]=buk2;
if(buk2==a[idx][pos2]) co;
res+=cnt[s];
}
s=a[idx];
s[pos]=buk;
}
}
s=a[idx];
for(char buk='a'; buk<='z'; buk++){
s[pos]=buk;
if(buk==a[idx][pos]) co;
for(int pos2=0; pos2<4; pos2++){
if(pos==pos2) co;
for(char buk2='0'; buk2<='9'; buk2++){
s[pos2]=buk2;
if(buk2==a[idx][pos2]) co;
res+=cnt[s];
}
for(char buk2='a'; buk2<='z'; buk2++){
s[pos2]=buk2;
if(buk2==a[idx][pos2]) co;
res+=cnt[s];
}
s=a[idx];
s[pos]=buk;
}
}
s=a[idx];
}
rt res;
}
void ibrosh_abi(){
cin>>n>>d;
for(int i=1; i<=n; i++){
cin>>a[i];
cnt[a[i]]++;
}
sort(a+1,a+n+1);
if(d==4){
cout<<(n*(n-1))/2<<nl;
rt;
}
for(int i=1; i<=n; i++){
if(d==1) dr1(i);
else if(d==2){
ans+=(dr2(i))/2;
}
}
cout<<ans/2;
}
signed main(){
ios_base::sync_with_stdio(false); cin.tie(0);
//open
int tt=1,cas=1;
//cin>>tt;
while(tt--){
//cout<<"Case "<<cas++<<": ";
ibrosh_abi();
}
}
