#include <bits/stdc++.h>
using namespace std;
struct edge
{
int to, cap, rev;
};
struct dinic
{
vector<int> level, it;
vector<vector<edge>> g;
int n;
dinic(int n) : n(n), level(n + 5), it(n + 5), g(n + 5) {}
void add_edge(int u, int v, int cap = 1)
{
edge a = {v, cap, (int)g[v].size()};
edge b = {u, 0, (int)g[u].size()};
g[u].push_back(a);
g[v].push_back(b);
}
bool bfs(int s, int t)
{
fill(level.begin(), level.end(), -1);
level[s] = 0;
queue<int> q;
q.push(s);
while (!q.empty())
{
int curr = q.front();
q.pop();
for (auto e : g[curr])
if (level[e.to] == -1 and e.cap > 0)
level[e.to] = level[curr] + 1, q.push(e.to);
}
return level[t] != -1;
}
int dfs(int curr, int t, int f)
{
if (curr == t)
return f;
for (int &i = it[curr]; i < g[curr].size(); i++)
{
auto &e = g[curr][i];
if (level[e.to] == level[curr] + 1 and e.cap > 0)
{
int push = dfs(e.to, t, min(f, e.cap));
if (push > 0)
{
e.cap -= push;
g[e.to][e.rev].cap += push;
return push;
}
}
}
return 0;
}
int max_flow(int s, int t)
{
int flow = 0;
cout << flow << '\n';
while (bfs(s, t))
{
fill(it.begin(), it.end(), 0);
while (int push = dfs(s, t, INT_MAX))
flow += push;
}
return flow;
}
};
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
int n, k;
cin >> n, k;
vector<int> l(2 * n), r(2 * n);
int st;
for (int i = 0; i < 2 * n; i++)
cin >> l[i] >> r[i] >> st;
int s = 0, e = 4 * n + 1;
dinic d(e);
for (int i = 1; i <= 2 * n; i++)
d.add_edge(s, i);
for (int i = 0; i < 2 * n; i++)
{
d.add_edge(i + 1, l[i] + (2 * n));
d.add_edge(l[i] + (3 * n), e);
d.add_edge(i + 1, r[i] + (3 * n));
d.add_edge(r[i] + (3 * n), e);
}
cout << (d.max_flow(s, e) == 2 * n ? "YES\n" : "NO\n");
return 0;
}
