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

#define REPU(i, a, b) for (int i = (a); i < (b); ++i)
#define REPD(i, a, b) for (int i = (a); i > (b); --i)
#define MEM(a, x) memset(a, x, sizeof(a))
#define ALL(a) a.begin(), a.end()
#define UNIQUE(a) a.erase(unique(ALL(a)), a.end())

typedef long long ll;
const int MOD = 1000000007;

template<class T> inline T tmin(T a, T b) { return (a < b) ? a : b; }
template<class T> inline T tmax(T a, T b) { return (a > b) ? a : b; }
template<class T> inline void amax(T &a, T b) { if (b > a) a = b; }
template<class T> inline void amin(T &a, T b) { if (b < a) a = b; }
template<class T> inline T tabs(T a) { return (a > 0) ? a : -a; }
template<class T> T gcd(T a, T b) { while (b != 0) { T c = a; a = b; b = c % b; } return a; }

int main(int argc, char *argv[]) {
	ios_base::sync_with_stdio(false);
	
	int n, x[11], y[11];

	cin >> n;
	REPU(i, 0, n) cin >> x[i] >> y[i];
	sort(x, x + n);
	sort(y, y + n);
	bool ok = (x[0] == x[n - 1]) || (y[0] == y[n - 1]);
	puts(ok ? "YES" : "NO");
	
	return 0;
}