#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using ll = long long;

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    int m, a, b, c;
    cin >> m;
    vector<pair<ll,int>> ca(3 * m);
    for(int i = 1, ci = 0; i <= m; i++){
        cin >> a >> b >> c;
        ca[ci++] = {(ll)(a) << 30 | b, i};
        ca[ci++] = {(ll)(b) << 30 | c, i};
        ca[ci++] = {(ll)(a) << 30 | c, -i};
    }
    sort(ca.begin(), ca.end());
    atcoder::dsu uf(2 * ++m);
    auto add = [&](int u, int v, int d){
        if(d >= 0)uf.merge(u, v), uf.merge(u + m, v + m);
        else uf.merge(u + m, v), uf.merge(u, v + m);
        if(uf.same(u, u + m)) cout << "NO\n", exit(0);
    };
    for(int r = 0; r < ca.size(); ){
        int l = r;
        while(r < ca.size() && get<0>(ca[r]) == get<0>(ca[l])) r++;
        for(int i = l; i < r; i++){
            auto [k1, v] = ca[i];
            for(int j = i + 1; j < r; j++){
                auto [k2, u] = ca[j];
                add(abs(v), abs(u), v ^ u ^ -1);
            }
        }
    }
    cout << "YES\n";
}