#include <bits/stdc++.h>
//qwerty47924692
using namespace std;
using ll = long long;
const ll N=2e5+29;
const string br="617283";
#define sz(a)(ll)a.size()
#define f first
#define s second
ll n,k,ans;
string s[N];
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
cin>>n>>k;
for(ll i=1;i<=n;i++){
cin>>s[i];
}for(ll i=1;i<=n;i++){
for(ll j=i+1;j<=n;j++){
for(ll l=j+1;l<=n;l++){
ll ok=1;
for(ll m=0;m<k;m++){
if(s[i]==s[j]&&s[j]==s[l])continue;
if(s[i]!=s[j]&&s[j]!=s[l]&&s[l]!=s[i])continue;
ok=0;
}ans+=ok;
}
}
}
cout<<ans;
}
