#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;

#ifndef ONLINE_JUDGE
#define dbg(x) cerr << __LINE__ << " : " << #x << " = " << (x) << endl;
#else
#define dbg(x)
#endif

#define ff first
#define ss second

int main(){
    std::ios_base::sync_with_stdio(false);
    int n; cin >> n;
    map<int, int> mx, my;
    for (int i = 0; i < n; i++){
        int x, y; cin >> x >> y;
        mx[x]++;
        my[y]++;
    }
    if ((int) mx.size() == 1 || (int) my.size() == 1) cout << "YES" << endl;
    else cout << "NO" << endl;

    return 0;
}