#include <bits/stdc++.h>
using namespace std;
const int block_size = 320;
const long long mod = 1e9 + 7;
const long long inf = 1e9 + 7;
const long double eps = 1e-9;
const double PI = atan(1) * 4;
template <typename T>
inline int sign(const T &a) {
  if (a < 0) return -1;
  if (a > 0) return 1;
  return 0;
}
string to_string(string s) { return '"' + s + '"'; }
string to_string(const char *s) { return to_string((string)s); }
string to_string(bool b) { return (b ? "true" : "false"); }
template <typename A, typename B>
string to_string(pair<A, B> p) {
  return "(" + to_string(p.first) + ", " + to_string(p.second) + ")";
}
template <typename A>
string to_string(A v) {
  bool first = true;
  string res = "{";
  for (const auto &x : v) {
    if (!first) {
      res += ", ";
    }
    first = false;
    res += to_string(x);
  }
  res += "}";
  return res;
}
void debug_out() { cerr << endl; }
template <typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
  cerr << " " << to_string(H);
  debug_out(T...);
}
template <typename T, typename S>
inline bool upmin(T &a, const S &b) {
  return a > b ? a = b, 1 : 0;
}
template <typename T, typename S>
inline bool upmax(T &a, const S &b) {
  return a < b ? a = b, 1 : 0;
}
template <typename T>
inline void in(T &x) {
  x = 0;
  T f = 1;
  char ch = getchar();
  while (!isdigit(ch)) {
    if (ch == '-') f = -1;
    ch = getchar();
  }
  while (isdigit(ch)) {
    x = x * 10 + ch - '0';
    ch = getchar();
  }
  x *= f;
}
long long twop(int x) { return 1LL << x; }
template <typename A, typename B>
inline void in(A &x, B &y) {
  in(x);
  in(y);
}
template <typename A, typename B, typename C>
inline void in(A &x, B &y, C &z) {
  in(x);
  in(y);
  in(z);
}
template <typename A, typename B, typename C, typename D>
inline void in(A &x, B &y, C &z, D &d) {
  in(x);
  in(y);
  in(z);
  in(d);
}
long long gcd(long long a, long long b) { return b == 0 ? a : gcd(b, a % b); }
namespace SOLVE {
int edge[40][40];
map<string, int> mp;
bitset<40> chosen;
int cnt = 0;
void main() {
  int n, m;
  in(n, m);
  vector<string> v;
  for (long long i = 0; i < n; i++) {
    string s;
    cin >> s;
    if (s == "1") {
      if (((int)v.size())) {
        sort(v.begin(), v.end());
        v.erase(unique(v.begin(), v.end()), v.end());
        for (auto s : v) {
          if (!mp.count(s)) mp[s] = cnt++;
        }
        for (long long i = 0; i < ((int)v.size()); i++) {
          for (long long j = i + 1; j < ((int)v.size()); j++) {
            edge[mp[v[i]]][mp[v[j]]] = 1;
            edge[mp[v[j]]][mp[v[i]]] = 1;
          }
        }
      }
      v.clear();
    } else {
      cin >> s;
      v.push_back(s);
    }
  }
  sort(v.begin(), v.end());
  v.erase(unique(v.begin(), v.end()), v.end());
  for (auto s : v) {
    if (!mp.count(s)) mp[s] = cnt++;
  }
  for (long long i = 0; i < ((int)v.size()); i++) {
    for (long long j = i + 1; j < ((int)v.size()); j++) {
      edge[mp[v[i]]][mp[v[j]]] = 1;
      edge[mp[v[j]]][mp[v[i]]] = 1;
    }
  }
  int ans = 0;
  vector<int> perm;
  for (long long i = 0; i < m; i++) perm.push_back(i);
  for (long long _ = 0; _ < 1000; _++) {
    random_shuffle(perm.begin(), perm.end());
    chosen.reset();
    for (auto i : perm) {
      bool ok = 1;
      for (long long j = 0; j < m; j++) {
        if (chosen[j] and edge[i][j]) {
          ok = 0;
          break;
        }
      }
      if (ok) chosen[i] = 1;
    }
    upmax(ans, chosen.count());
  }
  cout << ans << endl;
}
}  // namespace SOLVE
signed main() {
  int t;
  t = 1;
  while (t--) {
    SOLVE::main();
  }
  return 0;
}
