//time測定用
//構築未実装
#include <iostream>
#include <stdio.h>
#include <vector>
#include <algorithm>
#include <assert.h>
using namespace std;
#define ll long long

typedef struct edge3{
  ll to,cap,rev;
};


typedef struct FordFulkerson{
  const ll INF=1000000000000000000;
  ll MAX_V;
  vector<edge3>* G;
  bool* used;
  FordFulkerson(){}
  FordFulkerson(ll max_v){
    G=new vector<edge3>[max_v];
    used=new bool[max_v];
    MAX_V=max_v;
  }
  void add_edge(ll from,ll to,ll cap){
    G[from].push_back((edge3){to,cap,G[to].size()});
    G[to].push_back((edge3){from,0,G[from].size()-1});
  }
  ll dfs(ll v,ll t,ll f){
    if(v==t)return f;
    used[v]=true;
    for(int i=0;i<G[v].size();i++){
      edge3 &e=G[v][i];
      if(!used[e.to] && e.cap>0){
        ll d=dfs(e.to,t,min(f,e.cap));
        if(d>0){
          e.cap-=d;
          G[e.to][e.rev].cap+=d;
          return d;
        }
      }
    }
    return 0;
  }
  ll max_flow(ll s,ll t){
    ll flow=0;
    for(;;){
      fill(used,used+MAX_V,false);
      ll f=dfs(s,t,INF);
      if(f==0)return flow;
      flow+=f;
    }
    return flow;
  }
};

int main(){
  ll N,A,B;
  cin>>N;
  FordFulkerson F(200002);
  for(int i=0;i<N;i++){
    cin>>A>>B;
    A--;B--;
    F.add_edge(200000,i,1);
    F.add_edge(i,100000+A,1);
    if(A!=B)F.add_edge(i,100000+B,1);
    F.add_edge(100000+i,200001,1);
  }
  //cerr<<"edge added\n";
  ll cnt=F.max_flow(200000,200001);
  //cout<<cnt<<endl;
  if(cnt!=N){
    cout<<"No\n";
    return 0;
  }
  //ここから構築
  cout<<"Yes\n";
  return 0;
}