#include <fstream>
#include <iostream>
#include <string>
#include <complex>
#include <math.h>
#include <set>
#include <vector>
#include <map>
#include <queue>
#include <stdio.h>
#include <stack>
#include <algorithm>
#include <list>
#include <ctime>
#include <memory.h>
#include <assert.h>
#include <unordered_map>
#include <unordered_set>

#define bs 1000000007

static const int INF = 0x3f3f3f3f; 
static const long long INFL = 0x3f3f3f3f3f3f3f3fLL;

using namespace std;

int main() {

  int n; cin >> n;

  //vector<pair<int, int> > pts;
  unordered_set<int> xs;
  unordered_set<int> ys;
  for (int i = 0; i < n; i++) {
    int x, y; cin >> x >> y;
    //pts.push_back(make_pair(x, y));

    xs.insert(x);
    ys.insert(y);
  }
  if (xs.size() == 1 || ys.size() == 1) {
    cout << "YES" << endl;

  } else {
  cout << "NO"<< endl;
    
  }


  return 0;
}