#include<bits/stdc++.h>
#define ll long long
using namespace std;
int main()
{
    ll n;
    scanf("%lld",&n);
    ll m=n;
    ll x[21];
    ll y[21];
    ll x1,y1;
    for(ll i=0;i<21;i++)
        x[i]=y[i]=0;
    while(n--)
    {
        scanf("%lld %lld",&x1,&y1);
        x[x1+10]++;
        y[y1+10]++;
    }
    bool flag=false;
    for(ll i=0;i<21;i++)
        if(x[i]==m||y[i]==m)
        {
            flag=true;
            break;
        }
        if(flag)
            printf("YES\n");
        else
            printf("NO\n");
        return 0;
}