#include <bits/stdc++.h>
// solved by bekagg
#define ll long long
#define ent '\n'
#define pb push_back
#define all(x) x.begin(),x.end()
#define PRaim_bek_abi ios_base::sync_with_stdio(0);cin.tie(0);
using namespace std;
const int N = 1e5+5;
const int MOD = 1e9+7;
int n , d;
string g[N];
ll ans;
unordered_map<string , int>mp;
vector<char>v;
void arkanefury228(){
cin >> n >> d;
if (n <= 2000){
for (int i = 1; i <= n; i++){
cin >> g[i];
for (int j = 1; j < i; j++){
int sum = 0;
for (int k = 0; k < 4; k++){
if (g[i][k] != g[j][k]) sum++;
}
if (sum == d) ans++;
}
}
cout << ans;
return;
}
for (int i = 0; i <= 9; i++){
v.pb(char(i + '0'));
}
for (int i = 0; i < 26; i++){
v.pb(char(i + 'a'));
}
if (d == 0){
for (int i = 1; i <= n; i++){
string s;
cin >> s;
ans += mp[s];
}
cout << ans;
return;
}
if (d == 4){
for (int i = 1; i <= n; i++){
string s;
cin >> s;
}
cout << n * (n - 1) / 2;
return;
}
if (d == 1){
for (int i = 1; i <= n; i++){
string s;
cin >> s;
for (int j = 0; j < v.size(); j++){
string g = s;
g[0] = v[j];
ans += mp[g];
g[0] = s[0];
g[1] = v[j];
ans += mp[g];
g[1] = s[1];
g[2] = v[j];
ans += mp[g];
g[2] = s[2];
g[3] = v[j];
ans += mp[g];
g[3] = s[3];
}
mp[s]++;
}
cout << ans;
return;
}
if (d == 2){
for (int i = 1; i <= n; i++){
string s;
cin >> s;
for (int j = 0; j < v.size(); j++){
for (int k = 0; k < v.size(); k++){
string g = s;
g[0] = v[j];
g[1] = v[k];
ans += mp[g];
g[1] = s[1];
g[2] = v[k];
ans += mp[g];
g[2] = s[2];
g[3] = v[k];
ans += mp[g];
g[3] = s[3];
g[0] = s[0];
g[1] = v[j];
g[2] = v[k];
ans += mp[g];
g[2] = s[2];
g[3] = v[k];
ans += mp[g];
g[3] = s[3];
g[1] = s[1];
g[2] = v[j];
g[3] = v[k];
ans += mp[g];
}
}
mp[s]++;
}
cout << ans;
return;
}
}
signed main(){
PRaim_bek_abi
int t=1;
//cin>>t;
for (int respagold = 1; respagold <= t; respagold++) arkanefury228();
}
