#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 <cstdio>
#include <unordered_map>

using namespace std;

vector<pair<int, int> > v;
bool check() {
    bool mark = true;
    for (int i = 0; i < v.size(); ++i) {
        if (v[i].first != v[0].first) {
            mark = false;
            break;
        }
    }
    if (mark) {
        return true;
    }
    mark = true;
    for (int i = 0; i < v.size(); ++i) {
        if (v[i].second != v[0].second) {
            mark = false;
            break;
        }
    }
    return mark;
}

int main(){
    int n;
    cin >> n;
    int px, py;
    int mark = 0;
    for(int a0 = 0; a0 < n; a0++){
        int x;
        int y;
        scanf("%d%d", &x, &y);
        v.push_back(make_pair(x, y));
    }
    puts(check()?"YES":"NO");
    return 0;
}