#include <algorithm>
#include <array>
#include <bitset>
#include <complex>
#include <functional>
#include <iomanip>
#include <iostream>
#include <map>
#include <numeric>
#include <set>
#include <stack>
#include <unordered_map>
#include <unordered_set>
#include <queue>

using namespace std;

struct BoolName : numpunct<char> {
  string t, f;
  BoolName (string t = "Yes", string f = "No") : t(t), f(f) {}
  string do_truename() const {return t;}
  string do_falsename() const {return f;}
};

struct Initializer {
  Initializer() {
    cin.tie(0);
    ios::sync_with_stdio(0);
    cout << fixed << setprecision(15) << boolalpha;
    cout.imbue(locale(cout.getloc(), new BoolName));
  }
} initializer;

template<typename T> istream& operator>>(istream &s, vector<T> &v) {
  for (T &t : v) s >> t;
  return s;
}

template<typename T> ostream& operator<<(ostream &s, const vector<T> &v) {
  for (const T &t : v) s << t << endl;
  return s;
}

void set_bool_name(string t, string f) {
  cout.imbue(locale(cout.getloc(), new BoolName(t, f)));
}

template<typename T> bool chmin(T& a, T b) {return a > b ? a = b, true : false;}

template<typename T> bool chmax(T& a, T b) {return a < b ? a = b, true : false;}

template<typename T> void sort(vector<T>& v) {sort(v.begin(), v.end());}

template<typename T> T min(const vector<T>& v) {return *min_element(v.begin(), v.end());}

template<typename T> T max(const vector<T>& v) {return *max_element(v.begin(), v.end());}

template<typename T> int min_element(vector<T>& v) {return min_element(v.begin(), v.end()) - v.begin();}

template<typename T> int max_element(vector<T>& v) {return max_element(v.begin(), v.end()) - v.begin();}

template<typename T, typename Function> void sort(vector<T>& v, Function func) {sort(v.begin(), v.end(), func);}

template<typename T> void rsort(vector<T>& v) {sort(v.rbegin(), v.rend());}

template<typename T> void reverse(vector<T>& v) {reverse(v.begin(), v.end());}

template<typename T> void unique(vector<T>& v) {v.erase(unique(v.begin(), v.end()), v.end());}

template<typename T> void nth_element(vector<T>& v, int n) {nth_element(v.begin(), v.begin() + n, v.end());}

template<typename T> bool next_permutation(vector<T>& v) {return next_permutation(v.begin(), v.end());}

template<typename T> int find(vector<T>& v, T t) {return find(v.begin(), v.end(), t) - v.begin();}

template<typename T, typename S> int in(T v, S t) {return find(v.begin(), v.end(), t) != v.end();}

template<typename T> int lower_bound(vector<T>& v, T t) {return lower_bound(v.begin(), v.end(), t) - v.begin();}

template<typename T> int upper_bound(vector<T>& v, T t) {return upper_bound(v.begin(), v.end(), t) - v.begin();}

template<typename T, typename S = typename T::value_type, typename BinaryOperation> S accumulate(const T& v, S init, BinaryOperation func) {
  return accumulate(v.begin(), v.end(), init, func);
}

template<typename T, typename S = typename T::value_type> S accumulate(const T& v, S init = 0) {
  return accumulate(v.begin(), v.end(), init);
}

template<typename T> void adjacent_difference(vector<T>& v) {adjacent_difference(v.begin(), v.end(), v.begin());}

template<typename T> void adjacent_difference(vector<T>& v, vector<T>& u) {adjacent_difference(v.begin(), v.end(), u.begin());}

template<typename T> vector<T> partial_sum(const vector<T>& v) {
  vector<T> u(v.size());
  partial_sum(v.begin(), v.end(), u.begin());
  return u;
}

template<typename T> T inner_product(vector<T>& v, vector<T>& u) {return inner_product(v.begin(), v.end(), u.begin(), T(0));}

template<typename T> int count(const T& v, typename T::value_type t) {return count(v.begin(), v.end(), t);}

template<typename T, typename Function> int count_if(const vector<T>& v, Function func) {return count_if(v.begin(), v.end(), func);}

template<typename T, typename Function> void remove_if(vector<T>& v, Function func) {v.erase(remove_if(v.begin(), v.end(), func), v.end());}

template<typename T, typename Function> bool all_of(vector<T> v, Function func) {return all_of(v.begin(), v.end(), func);}

template<typename T, typename Function> bool any_of(vector<T> v, Function func) {return any_of(v.begin(), v.end(), func);}

template<typename T, typename Function> bool none_of(vector<T> v, Function func) {return none_of(v.begin(), v.end(), func);}

template<typename T> vector<T> subvector(vector<T>& v, int a, int b) {return vector<T>(v.begin() + a, v.begin() + b);}

template<typename T> int kinds(const T& v) {return set<typename T::value_type>(v.begin(), v.end()).size();}

template<typename T> map<typename T::value_type, int> count_kinds(const T& v) {
  map<typename T::value_type, int> res;
  for (const auto& i : v) ++res[i];
  return res;
}

template<typename T> void iota(vector<T>& v, T t = 0) {iota(v.begin(), v.end(), t);}

template<typename T> bool is_sorted(const vector<T>& v) {return is_sorted(v.begin(), v.end());}

template<typename T> unordered_map<T, int> coordinateCompression(vector<T> v) {
  sort(v);
  unique(v);
  unordered_map<T, int> res;
  for (unsigned i = 0; i < v.size(); ++i) res.emplace(v[i], i);
  return res;
}

template<typename Value> class CumulativeSum1D {
private:
  struct RangeValue {
    int i, j;
    Value v;
    RangeValue(int i, int j, Value v) : i(i), j(j), v(v) {}
  };

  vector<Value> val;
  vector<RangeValue> rangeValue;

public:
  CumulativeSum1D(int n) : val(n + 2) {}

  CumulativeSum1D(size_t n) : val(n + 2) {}

  template<typename T> CumulativeSum1D(T v) : val(v.size() + 2) {
    partial_sum(v.begin(), v.end(), val.begin() + 1);
  }

  void add(int i, Value v) {
    add(i, i + 1, v);
  }

  void add(int i, int j, Value v) {
    rangeValue.emplace_back(i, j, v);
  }

  // [i,j)
  Value sum(int i, int j) {
    if (!rangeValue.empty()) {
      adjacent_difference(val.begin(), val.end(), val.begin());
      adjacent_difference(val.begin(), val.end(), val.begin());
      for (const auto& v : rangeValue) {
        val[v.i + 1] += v.v;
        val[v.j + 1] -= v.v;
      }
      partial_sum(val.begin(), val.end(), val.begin());
      partial_sum(val.begin(), val.end(), val.begin());
      rangeValue.clear();
    }
    return val[j] - val[i];
  }

  Value value(int i) {
    return sum(i, i + 1);
  }

  Value max() {
    auto res = numeric_limits<Value>::min();
    for (int i = 0; i < int(val.size()) - 2; ++i) chmax(res, value(i));
    return res;
  }
};

int main() {
  int n, c;
  cin >> n >> c;
  vector<tuple<int, int, int>> v, u;
  for (int i = 0; i < n; ++i) {
    int s, t, k;
    cin >> s >> t >> k;
    v.emplace_back(k, s, t);
  }
  sort(v);
  u.emplace_back(v[0]);
  for (int i = 1; i < n; ++i) {
    if (get<1>(v[i]) == get<2>(u.back()) && get<0>(v[i]) == get<0>(u.back())) {
      get<2>(u.back()) = get<2>(v[i]);
    } else {
      u.emplace_back(v[i]);
    }
  }
  vector<int> w;
  for (auto i : u) {
    w.emplace_back(2 * get<1>(i) - 1);
    w.emplace_back(2 * get<2>(i));
  }
  auto coord = coordinateCompression(w);
  CumulativeSum1D<int> sum(coord.size());
  for (auto i : u) sum.add(coord[2 * get<1>(i) - 1], coord[2 * get<2>(i)], 1);
  cout << sum.max() << endl;
}



Measured memory_bytes: 12824