//============================================================================
// Author      : Prateek Agarwal
// Institution : NITJ
//============================================================================

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

#define TEST int t;scan(t);while(t--)
#define scan(n) scanf("%d",&n)
#define set(x,y) memset(x,y,sizeof(x))
#define loop(i,l,r,x) for (int i=l;i<=r;i+=x)
#define printl(n) printf("%d\n",n)
#define print(n) printf("%d ",n)
#define pb push_back

#define INF 1000000001
#define M 1000000007
#define MAX 100001


int init(){
	int n;
	scan(n);
	int x[n],y[n];
	loop(i,0,n-1,1) cin>>x[i]>>y[i];
	int f = 0;
	loop(i,0,n-1,1){
		if (x[i]!=x[0]){
			f = 1;
			break;
		}
	}

	if (f==0){
		cout << "YES\n";
		return 0;
	}

	f = 0;

	loop(i,0,n-1,1){
		if (y[i]!=y[0]){
			f = 1;
			break;
		}
	}
	if (f==0){
		cout << "YES\n";
		return 0;
	}
	cout << "NO\n";
	return 0;
}

int main(){
	//clock_t start = clock();
	init();
	//printf("%.6f\n",double(clock()-start)/CLOCKS_PER_SEC);
	return 0;
}