#include<bits/stdc++.h>
using namespace std;
using ll=long long;
int main(){
	ll n;
	cin>>n;
	bool ans=0;
	vector<pair<ll,ll>> v;
	v.push_back({0,0});
	for(int i=0;i<n;i++){
		ll a,b;
		cin>>a>>b;
		v.push_back({a,b});
	}
	sort(v.begin(),v.end());
	for(int i=0;i<n-1;i++){
		if(v[i].first+1==v[i+1].first&&v[i].second<v[i+1].second){
			cout<<"Yes"<<endl;
			return 0;
		}
	}
	cout<<"No"<<endl;
}