// *****************************************//
//            Rachit Garg                   //
// *****************************************//
#include<bits/stdc++.h>
#define f(i,l,r) for(i=l;i<r;i++)
#define fr(i,r,l) for(i=r;i>l;i--)
#define s(n) scanf("%lld",&n)
#define pl(n) printf("%lld\n",n)
#define ss(s) scanf("%s",s);
#define sz size()
#define ll long long int
#define pb push_back
#define mp make_pair
#define vll vector<ll>
#define pll pair<ll,ll>
#define F first
#define S second
#define mod 1000000007
#define maxa 1000005
#define maxv 1000000009
#define pi 3.14159265358979323846
#define all(v) v.begin() , v.end()
using namespace std;
int main(){
    ll n,m,i,j,flag1,flag2,x,y;
    vector< pll > v;
    s(n);
    f(i,0,n){
        s(x),s(y);
        v.pb(mp(x,y));
    }
    flag1 = 0;
    flag2 = 0;
    x = v[0].F;
    f(i,1,(ll)v.size()){
        if(v[i].F != x){
            flag1 = 1;
            break;
        }
    }
    y = v[0].S;
    f(i,1,(ll)v.size()){
        if(v[i].S != y){
            flag2 = 1;
            break;
        }
    }
    if(flag1 == 0 || flag2 == 0)
        printf("YES\n");
    else
        printf("NO\n");
    return 0;
}