This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
using namespace std;
using namespace __gnu_pbds;
#define F first
#define S second
#define forn(i, n) for(int i = 0; i < n; ++i)
#define forbn(i, b, n) for(int i = b; i < n; ++i)
#define sz(v) (int)v.size()
#define pb push_back
#define mp make_pair
#define eb emplace_back
#define all(v) v.begin(), v.end()
#define min3(a, b, c) min(a, min(b, c))
#define lc v << 1
#define rc (v << 1) + 1
typedef pair<int, int> ii;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef long long ll;
typedef complex<double> cd;
typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;
template <class T> inline void mineq(T &a, T b) { a = min(a, b); }
template <class T> inline void maxeq(T &a, T b) { a = max(a, b); }
const int MX = 30 * 1000 + 5;
int l[MX], r[MX], s[MX];
set<int> sp2id[2 * MX];
void solve() {
	int n, k;
	cin >> n >> k;
	forn(i, 2 * n) {
		cin >> l[i] >> r[i] >> s[i];
		l[i]--; r[i]--;
		sp2id[l[i]].insert(i);
		sp2id[r[i] + n].insert(i);
	}
	set<ii> q;
	forn(sp, 2 * n) {
		q.insert({sz(sp2id[sp]), sp});
	}
	while(!q.empty() && q.begin()->F < 2) {
		int ss = q.begin()->F, sp = q.begin()->S;
		if(ss == 0) {
			cout << "NO\n";
			return;
		}
		int i = *sp2id[sp].begin();
		int sp2 = sp == l[i] ? r[i] + n : l[i];
		q.erase({sz(sp2id[sp]), sp});
		q.erase({sz(sp2id[sp2]), sp2});
		sp2id[sp].erase(i);
		sp2id[sp2].erase(i);
		q.insert({sz(sp2id[sp2]), sp2});
	}
	cout << "YES\n";
}
int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(nullptr);
	cout.tie(nullptr);
//	freopen("triangles.in", "r", stdin);
//	freopen("triangles.out", "w", stdout);
	int t = 1;
//	cin >> t;
	while(t--) {
		solve();
	}
}
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