#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
#include <map>
using namespace std;


int main() {
    int n;
    cin >> n;
    map<int, int> x, y;
    for(int i = 0; i < n; i++)
        {
        int xx, yy;
        cin >> xx >> yy;
        x[xx]++;
        y[yy]++;
}
    if(x.size() == 1 || y.size() == 1)
        cout << "YES\n";
    else
        cout << "NO\n";
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */   
    return 0;
}