#include <bits/stdc++.h>
#include <sys/time.h>
#define FOR(i, min, max) for (int i = (min); i < (max); ++i) 
#define FORE(i, min, max) for (int i = (min); i <= (max); ++i)
#define DFOR(i,max,min) for(int i=(max);i>(min);--i)
#define DFORE(i,max,min) for(int i=(max);i>=(min);--i)
#define REP(i, n) for (int i = 0; i < (n); ++i)
#define DREP(i, n) for (int i = (n); i >=0; --i) 
#define REPV(vec, i) for (int i = 0; i < (int)(vec.size()); ++i) 
#define FOR_EACH(vec, it) for (auto it = (vec).begin(); it != (vec).end(); ++it)
#define LL long long int
using namespace std;
namespace std {
  template <typename T>
  class hash<std::pair<T, T>> {
  public:
    size_t operator()(const std::pair<T, T>& x) const{
      return hash<T>()(x.first) ^ hash<T>()(x.second);
    }
  };
}

class Clock{
public:
  double startTime;
  double getTime(){
    timeval tv;
    gettimeofday(&tv,NULL);
    return tv.tv_sec+tv.tv_usec*1e-6;
  }
  void start(){
    startTime=getTime();
  }
  double now(){
    return getTime()-startTime;
  }
};

vector<string> split(const string &str, char delim=' '){
  vector<string> res;
  size_t current = 0, found;
  while((found = str.find_first_of(delim, current)) != string::npos){
    res.push_back(string(str, current, found - current));
    current = found + 1;
  }
  res.push_back(string(str, current, str.size() - current));
  return res;
}
template<typename Ret>
string join(vector<Ret> ss,string d=" "){
  ostringstream os;
  for(int i=0;i<ss.size();i++){
    os << ss[i];
    if(i!=ss.size()-1)os << d;
  }
  return os.str();
}
string readAll(){
  istreambuf_iterator<char> it(cin);
  istreambuf_iterator<char> last;
  string str(it, last);
  return str;
}
int readInt(){
  int n;
  cin >> n;
  return n;
}
template<typename Ret>
string str(const Ret& n){
  ostringstream os;
  os << n;
  return os.str();
}
//use readVector<int>(int n)
template<typename Ret>
vector<Ret> readVector(int n){
  vector<Ret> v(n);
  REP(i,n){
    cin >> v[i];
  }
  return v;
}
vector<int> readInts(int n){
  string s;
  getline(cin,s);
  vector<string> ss=split(s);
  vector<int> v(n);
  REP(i,n){
    v[i]=atoi(ss[i].c_str());
  }
  return v;
}
int main(){
  int n;
  cin >> n;
  set<int> xs;
  set<int> ys;
  REP(i,n){
    int x,y;
    cin >> x >> y;
    xs.insert(x);
    ys.insert(y);
  }
  if(xs.size()==1||ys.size()==1){
    cout << "YES" << endl;
  }else{
    cout << "NO" << endl;
  }
  return 0;
}