#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <iomanip>
#include <array>
#include <string>
#include <algorithm>
#include <cmath>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <vector>
#include <stack>
#include <queue>
#include <deque>
#include <bitset>
#include <list>
#include <iterator>
#include <numeric>
#include <complex>
#include <utility>
#include <random>
#include <cassert>
#include <fstream>
using namespace std;
mt19937 rnd(time(nullptr));
/* -------------------- Typedefs -------------------- */
typedef int itn;
typedef long long ll;
typedef unsigned long long ull;
typedef double db;
typedef float fl;
typedef long double ld;
/* -------------------- Usings -------------------- */
using vi = vector<int>;
using vll = vector<ll>;
using mii = map<int, int>;
using mll = map<ll, ll>;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
/* -------------------- Defines -------------------- */
#define ff first
#define ss second
#define pub push_back
#define pob pop_back
#define puf push_front
#define pof pop_front
#define mpr make_pair
#define yes cout<<"Yes\n"
#define no cout<<"No\n"
#define all(x) (x).begin(), (x).end()
#define USACO freopen("feast.in", "r", stdin); freopen("feast.out", "w", stdout);
/* -------------------- Constants -------------------- */
const int dx[8] = { -1, 0, 1, 0, -1, -1, 1, 1 };
const int dy[8] = { 0, -1, 0, 1, -1, 1, -1, 1 };
const int MAX = int(1e9 + 5);
const ll MAXL = ll(1e18) + 5ll;
const ll MOD = ll(1000000007);
const ll MOD2 = ll(998244353);
/* -------------------- Functions -------------------- */
void fastio() {
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
}
void precision(int x) {
cout.setf(ios::fixed | ios::showpoint);
cout.precision(x);
}
ll gcd(ll a, ll b) {
if (a == 0 || b == 0) return(max(a, b));
while (b) {
a %= b;
swap(a, b);
}
return a;
}
ll lcm(ll a, ll b) {
return a / gcd(a, b) * b;
}
ll range_sum(ll a, ll b) {
if (a > b) return 0ll;
ll dif = a - 1, cnt = b - a + 1;
ll ans = ((b - a + 1) * (b - a + 2)) / 2;
ans += ((b - a + 1) * dif);
return ans;
}
string dec_to_bin(ll a) {
string s = "";
for (ll i = a; i > 0; ) {
ll k = i % 2;
i /= 2;
char c = k + 48;
s += c;
}
if (a == 0) {
s = "0";
}
reverse(all(s));
return s;
}
ll bin_to_dec(string s) {
ll num = 0;
for (int i = 0; i < s.size(); i++) {
num *= 2ll;
num += (s[i] - '0');
}
return num;
}
ll factorial_by_mod(ll n, ll mod) {
ll ans = 1;
ll num;
for (ll i = 1; i <= n; ++i) {
num = i % mod;
ans *= num;
ans %= mod;
}
return ans;
}
bool isPrime(ll a) {
if (a == 1) return false;
for (ll i = 2; i * i <= a; i++) {
if (a % i == 0) return false;
}
return true;
}
ll binpow(ll a, ll b) {
if (!a) return 0;
ll ans = 1;
while (b) {
if (b & 1) {
ans *= a;
}
b >>= 1;
a *= a;
}
return ans;
}
ll binpow_by_mod(ll a, ll b, ll mod) {
if (!a) return 0;
ll ans = 1;
while (b) {
if (b & 1) {
ans *= a;
ans %= mod;
}
b >>= 1;
a *= a;
a %= mod;
}
return ans;
}
/* -------------------- Solution -------------------- */
const int N = 500005, M = (1 << 4) + 5;
string a[N];
ll a_hash[N], ans[M], han[M];
ll p = 31;
int n, k, m = 4;
ll count(int mask) {
ll p_pow = 1, num;
char c;
for (int i = 1; i <= n; ++i) {
a_hash[i] = 0;
p_pow = 1;
for (int bit = 0; bit < m; ++bit) {
if ((1 << bit) & mask) {
continue;
}
c = a[i][bit];
if (c >= 'a' && c <= 'z') {
num = c - 'a';
++num;
}
else {
num = c - '0';
num += 27;
}
a_hash[i] += p_pow * num;
a_hash[i] %= MOD;
p_pow *= p;
p_pow %= MOD;
}
}
sort(a_hash + 1, a_hash + n + 1);
ll ret = 0;
ll cnt = 1;
for (int i = 2; i <= n; ++i) {
if (a_hash[i] == a_hash[i - 1]) {
++cnt;
continue;
}
ret += (cnt * (cnt - 1ll)) / 2ll;
cnt = 1;
}
ret += (cnt * (cnt - 1ll)) / 2;
return ret;
}
void slv() {
cin >> n >> k;
for (int i = 1; i <= n; ++i) {
cin >> a[i];
}
ll answ = 0;
for (int mask = 0; mask < (1 << m); ++mask) {
ans[mask] = count(mask) - han[mask];
for (int mask1 = 0; mask1 < (1 << m); ++mask1) {
if (mask == mask1) continue;
bool f = true;
for (int bit = 0; bit < m; ++bit) {
int bit1 = 0, bit2 = 0;
if ((1 << bit) & mask) bit1 = 1;
if ((1 << bit) & mask1) bit2 = 1;
if (bit1 == 1 && bit2 == 0) {
f = false;
break;
}
}
if (f) {
han[mask1] += ans[mask];
}
}
int number_of_ones = 0;
for (int bit = 0; bit < m; ++bit) {
if ((1 << bit) & mask) {
++number_of_ones;
continue;
}
han[(1 << bit) | mask] += ans[mask];
}
ans[mask] -= han[mask];
if (number_of_ones == k) {
answ += ans[mask];
}
}
cout << answ;
}
/*
3 2
0011
1100
0011
*/
void cs() {
int tstc = 1;
//cin >> tstc;
while (tstc--) {
slv();
}
}
void precalc() {
return;
}
int main() {
fastio();
precalc();
//precision(0);
cs();
return 0;
}
