#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 i,x[10000],y[10000];
bool yes,ans;

int main(){
    int n;
    cin >> n;
    for(int a0 = 0; a0 < n; a0++){
        scanf("%d%d",&x[a0],&y[a0]);
    }
    
    ans = false;
    yes = true;
    for (i=0 ; i<n ; i++) if (x[i] != x[0]) yes = false;
    ans |= yes;
    yes = true;
    for (i=0 ; i<n ; i++) if (y[i] != y[0]) yes = false;
    ans |= yes;
    
    if (ans) printf("YES\n"); else printf("NO\n");
    
    return 0;
}