#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
//const long nPrime = 1000000007;
//const long nPrime = 998244353;
typedef long long ll;
int main() {
    ll n;
    cin >> n;
    for(ll i = 0; i < n; i++){
        ll v,w;
        cin >> v >> w;
        if(w == 1){
            cout << "Yes" << endl;
            return 0;
        }
    }
    cout << "No" << endl;
     return 0;
}