#include    <bits/stdc++.h>

#define     M_PI            3.14159265358979323846
#define     mod             1000000007
#define     inf             1000000000000000000
#define     mp              make_pair
#define     pb              push_back
#define     eb              emplace_back
#define     F               first
#define     S               second
#define     ll              long long
#define     pii             pair<int,int>
#define     pli             pair<ll,int>
#define     pil             pair<int,ll>
#define     pll             pair<ll,ll>
#define     rep(i,a)        for(__typeof(a) i=0;i<a;i++)
#define     REP(i,a,b)      for(__typeof(a) i=a;i<=b;i++)
#define     RREP(i,a,b)     for(__typeof(a) i=a;i>=b;i--)
#define     endl            '\n' 
#define     N               55

using namespace std;

pii arr[N];
int n;

int funx(){
    if(n == 1) return 1;
    REP(i,1,n-1) if(arr[i].F != arr[i-1].F ) return 0;
    return 1;
}

int funy(){
    if(n==1) return 1;
    REP(i,1,n-1) if(arr[i].S != arr[i-1].S ) return 0;
    return 1;
}

int main(){
    std::ios::sync_with_stdio(false); 
    cin>>n;
    rep(i,n) cin>>arr[i].F>>arr[i].S;
    int f = funx();
    int g = funy();
    if(f || g) cout << "YES" << endl;
    else cout << "NO" << endl;
    return 0;
}