#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;
    cin >> m;
    vector<tuple<int,int,int>> a(m);
    vector<int> ca;
    for(auto &&[A, B, C] : a){
        cin >> A >> B >> C;
        ca.emplace_back(A);
        ca.emplace_back(B);
        ca.emplace_back(C);
    }
    sort(ca.begin(), ca.end());
    ca.erase(unique(ca.begin(), ca.end()), ca.end());
    vector<int> cnt(ca.size());
    for(auto &&[A, B, C] : a){
        A = lower_bound(ca.begin(), ca.end(), A) - ca.begin();
        B = lower_bound(ca.begin(), ca.end(), B) - ca.begin();
        C = lower_bound(ca.begin(), ca.end(), C) - ca.begin();
        cnt[A]++, cnt[B]++, cnt[C]++;
    }
    for(auto &&[A, B, C] : a){
        if(cnt[A] != cnt[B] || cnt[A] != cnt[C]){
            cout << "NO\n";
            return 0;
        }
    }
    cout << "YES\n";
}