#include <bits/stdc++.h> 

using namespace std; 
#define forn(i, n) for (int i = 0; i < n; i++)
#define re return
#define sz(a) (int)a.size()
#define fi first
#define se second
#define mp(a, b) make_pair(a, b)
#define gi get_int() 
#define x1 xxx111
#define y1 yyy111
typedef long long ll;
typedef double ld;
typedef pair<ld, ld> pld;
typedef vector<ll> vi;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

const ll cnn = 800, md = 1000000007, sz_g = 200000, pq = 100000000, inf = 1000000000LL,
 mod2 = 5000000, ma = 128 * 1024, ma1 = 8, inf11 = 5LL * inf * inf;

void my_assert() {
	while(true);
}
ll llabs(ll k) {
	if (k < 0) re -k;
	re k;
}
ll get_int() {
	int n;
	scanf("%d", &n);
	re n;
}

int main() {
    iostream::sync_with_stdio(0), cin.tie(0);
    //freopen("sum.in", "r", stdin);
    //freopen("kingrook.out", "w", stdout);
    int n = gi;
    vector<pii> b(n);
    forn (i, n) {
    	b[i].fi = gi; b[i].se = gi;
    }
    bool ok1 = true, ok2 = true;
    forn (i, n)
    	if (b[i].fi != b[0].fi) ok1 = false;
    forn (i, n)
    	if (b[i].se != b[0].se) ok2 = false;
    if (ok1 || ok2) {
    	cout << "YES\n";
    }
    else cout << "NO\n";
    return 0;
}