#include <map>
#include <set>
#include <list>
#include <cmath>
#include <ctime>
#include <deque>
#include <queue>
#include <stack>
#include <string>
#include <bitset>
#include <cstdio>
#include <limits>
#include <vector>
#include <climits>
#include <cstring>
#include <cstdlib>
#include <fstream>
#include <numeric>
#include <sstream>
#include <iostream>
#include <algorithm>
#include <unordered_map>

using namespace std;


int main(){
    int n;
    cin >> n;
   int x0, y0;
   cin >> x0 >> y0;
   bool o[2] = {1, 1};
    for(int a0 = 0; a0 < n; a0++){
        int x;
        int y;
        cin >> x >> y;
       if(x != x0)
          o[0] = 0;
       if(y != y0)
          o[1] = 0;
    }
   cout << (o[0] | o[1] ? "YES" : "NO") << endl;
    return 0;
}