/*yukicoder April Fool Contest 2022 C*/
#include<bits/stdc++.h>
using namespace std;

int main(){
  int n,v,w;
  cin>>n;
  while(n--){
    cin>>v>>w;
    if(w==1){
      cout<<"Yes\n";
      return 0;
    }
    
  }
  
  cout<<"No\n";
  return 0;
}