#include<bits/stdc++.h>
#define ll long long
#define fi first
#define se second
ll mpow(ll a, ll n,ll mod)
{ll ret=1;ll b=a;while(n) {if(n&1)
    ret=(ret*b)%mod;b=(b*b)%mod;n>>=1;}
return (ll)ret;
}
using namespace std;
#define sd(x) scanf("%d",&x)
#define pd(x) printf("%d",x)
#define mem(x,a) memset(x,a,sizeof(x))
#define pii pair<int,int>
#define mp make_pair
#define pb push_back
#define all(v) v.begin(),v.end()
#define N (int)(1e6+5)
using namespace std;
void solve(){
   int n;
   sd(n);
   int initx=-1e9,inity=-1e9;
   int ftx=0,fty=0;
   while(n--){
    int x,y;
    sd(x);sd(y);
    if(initx==-1e9){
        initx=x;
        inity=y;
        continue;
    }
    if(x!=initx){
        ftx++;
    }
    if(y!=inity){
        fty++;
    }
   }
   if(ftx&&fty){
    printf("NO\n");
   }
   else{
    printf("YES\n");
   }
}
int main(){
   //freopen("input.IN","r",stdin);
   //freopen("out.txt","w",stdout);
   int t=1;
   //scanf("%d",&t);
   for(int i=1;i<=t;i++){
       //printf("Case #%d:\n",i);
       solve();
   }
   return 0;
}