#include <bits/stdc++.h>
using namespace std;

#define sd(a) scanf("%d", &a)
#define ss(a) scanf("%s", a)
#define sl(a) scanf("%lld", &a)
#define clr(a) memset(a, 0, sizeof(a))
#define debug(a) printf("check %d\n", a)
#define F first
#define S second
#define PB push_back
#define ll long long
#define flush() fflush(stdout)
#define rep(i,n) for ( int i = 0 ; i < n ; i++ )

typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int,int> ii;
typedef vector<ii> vii;
typedef vector<vii> vvii;

struct Point
{
    int x;
    int y;
};
 
vector<Point> points; 

int orientation(Point p, Point q, Point r)
{
    // See http://www.geeksforgeeks.org/orientation-3-ordered-points/
    // for details of below formula.
    int val = (q.y - p.y) * (r.x - q.x) -
              (q.x - p.x) * (r.y - q.y);
 
    if (val == 0) return 0;  // colinear
 
    return (val > 0)? 1: 2; // clock or counterclock wise
}

int main()
{
	// freopen("input.in", "r", stdin);
	int n;
	sd(n);
	for ( int i = 0 ; i < n ; i++ )
	{
		int x, y;
		sd(x); sd(y);
		Point p; 
		p.x = x; p.y = y;
		points.push_back(p);
	}
	bool hori = true, verti = true;
	for ( int i = 1 ; i < points.size() ; i++ )
	{
		if (points[i].x != points[i-1].x)
		{
			verti = false;
			break;
		}
	}
	for ( int i = 1 ; i < points.size() ; i++ )
	{
		if (points[i].y != points[i-1].y)
		{
			hori = false;
			break;
		}
	}
	if ( verti || hori )
		printf("YES");
	else
		printf("NO");
}