#include<bits/stdc++.h>
using namespace std;
using ll = long long;
using ull = unsigned long long;
const long long MOD = 1000000007;
const long double PI = 3.14159265358979;
const long long INF = 1LL<<60;
template <typename T> bool chmax(T &a, const T& b){if(a < b){a = b;return true;}return false;}
template <typename T> bool chmin(T &a, const T& b){if(a > b){a = b;return true;}return false;}
bool is_prime(long long N){if(N==1) return false;for(long long i=2; i*i <= N; i++){if(N%i==0)return false;}return true;}
long long gcd(long long a, long long b){if (b == 0) return a;else return gcd(b, a % b);}
template<typename T> using min_priority_queue = priority_queue<T, vector<T>, greater<T>>;
#define int long long


int32_t main(){
    int N;
    cin >> N;
    vector<int> ans, nurinuri(N,0);
    for(int i=0; i<N; i++){
        int a,b; cin >> a >> b;
        a--; b--;
        if(!nurinuri[a]){
            nurinuri[a]=1;
            ans.push_back(a);
        }else{
            nurinuri[b] = 1;
            ans.push_back(b);
        }
    }
    for(int i=0; i<N; i++){
        if(!nurinuri[i]){
            cout << "No" << endl;
            return 0;
        }
    }
    cout << "Yes" << endl;
    for(int i=0; i<N; i++){
        cout << ans[i]+1 << endl;
    }
}