#include <map>
#include <set>
#include <list>
#include <cmath>
#include <ctime>
#include <deque>
#include <queue>
#include <stack>
#include <string>
#include <bitset>
#include <cstdio>
#include <limits>
#include <vector>
#include <climits>
#include <cstring>
#include <cstdlib>
#include <fstream>
#include <numeric>
#include <sstream>
#include <iostream>
#include <algorithm>
#include <unordered_map>

using namespace std;


int main(){
    int n;
    cin >> n;
    
    vector<int> x(n, 0), y(n, 0);
    
    for (int  i = 0; i < n; ++i) {
        cin >> x[i] >> y[i];    
    }
    
    bool neq = false;
    for (int i = 1; i < n; ++i) {
        if (x[0] != x[i]) {
            neq = true;
            break;
        }
    }
    
    if (neq == false) {
        cout << "YES";
    }
    else {
        neq = false;
        for (int i = 1; i < n; ++i) {
            if (y[0] != y[i]) {
                neq = true;
                break;
            }
        }
        
        if (neq == false) {
            cout << "YES";
        }
        else {
            cout << "NO";
        }
    }
    /*
    int x1, y1, x2, y2;
    cin >> x1 >> y1;
    cin >> x2 >> y2;
    
    bool ex = false, ey = false, noe = false;
    if (x1 == x2) {
        ex = true;
    }
    else if (y1 == y2) {        
        ey = true;
    }
    else {
        noe = true;
    }
    
    if (noe) {
        cout << "NO" << endl;
    }
    else {
        bool flag = false;
        for(int a0 = 0; a0 < n; a0++){
            int x;
            int y;
            cin >> x >> y;
            
            if (ex && x != x2) {     
                flag = true;
                break;
            }
            else if (ey && y != y2) { 
                flag = true;
                break;
            }            
        }
        
        if (flag == false) {
            cout << "YES" << endl;
        }
        else {
            cout << "NO" << endl;
        }
    }
    return 0;
    */
}