#include <bits/stdc++.h>
#define range(i, l, r) for(int (i) = (l); (i) < (r); (i)++)
#define reversed_range(i, l, r) for (int (i) = (r) - 1; (i) >= l; (i)--)
using namespace std;
template <typename T>
using vec = vector<T>;
using lint = long long;
using ulint = unsigned long long;
using pint = pair<int, int>;
using plint = pair<lint, lint>;

template <typename S, typename T>
ostream& operator <<(ostream& os, pair<S, T> p) {
    os << "(";
    os << p.first << ", " << p.second;
    return os << ")";
}

template <typename T>
ostream& operator <<(ostream& os, vec<T> v) {
    os << "[";
    for (int i = 0; i < v.size() - 1; i++) {
        os << v.at(i) << ", ";
    }
    return os << v.at(v.size() - 1) << "]";
}

template <typename T>
ostream& operator <<(ostream& os, set<T>& s) {
    os << "{";
    auto it_first_item = s.begin();
    cout << *it_first_item;
    for (auto it = ++it_first_item; it != s.end(); it++) {
        cout << ", " << *it;
    }
    return cout << "}";
}

template <typename T>
ostream& operator <<(ostream& os, unordered_set<T>& s) {
    os << "{";
    auto it_first_item = s.begin();
    cout << *it_first_item;
    for (auto it = ++it_first_item; it != s.end(); it++) {
        cout << ", " << *it;
    }
    return cout << "}";
}

template <typename K, typename V>
ostream& operator <<(ostream& os, map<K, V> m) {
    os << "{";
    auto it_first_item = m.begin();
    cout << it_first_item->first << ": " << it_first_item->second;
    for (auto it = ++it_first_item; it != m.end(); it++) {
        cout << ", " << it->first << ": " << it->second;
    }
    return os << "}";
}

template <typename K, typename V>
ostream& operator <<(ostream& os, unordered_map<K, V> m) {
    os << "{";
    auto it_first_item = m.begin();
    cout << it_first_item->first << ": " << it_first_item->second;
    for (auto it = ++it_first_item; it != m.end(); it++) {
        cout << ", " << it->first << ": " << it->second;
    }
    return os << "}";
}

int main() {
    cin.tie(0); cout.tie(0);
    ios::sync_with_stdio(false);
    lint N, C;
    cin >> N >> C;
    vec<vec<lint>> programs(N);
    range(i, 0, N) {
        lint s, t, c;
        cin >> s >> t >> c;
        c -= 1;
        programs.at(i) = {s, t, c};
    }
    vec<vec<bool>> is_new_program_starting(100000 + 1, vec<bool>(C, false)), is_program_ending(100000 + 1, vec<bool>(C, false));
    for (const auto program : programs) {
        lint s = program.at(0), t = program.at(1), c = program.at(2);
        is_new_program_starting.at(s).at(c) = true;
        is_program_ending.at(t).at(c) = true;
    }
    lint cur_num_recoders = 0;
    lint max_num_recoders = 0;
    vec<bool> is_on(C, false);
    range(t, 0, 100000 + 1) {
        range(c, 0, C) {
            if (!is_on.at(c) && is_new_program_starting.at(t).at(c)) {
                is_on.at(c) = true;
                cur_num_recoders += 1;
            }
        }
        max_num_recoders = max(max_num_recoders, cur_num_recoders);
        range(c, 0, C) {
            if (is_program_ending.at(t).at(c) && !is_new_program_starting.at(t).at(c)) {
                is_on.at(c) = false;
                cur_num_recoders -= 1;
            }
        }
    }
    cout << max_num_recoders << "\n";
}

Measured memory_bytes: 19840