#include <stdio.h>
#include <bits/stdc++.h>
#include <atcoder/all>
using namespace atcoder;
using mint = modint998244353;
using namespace std;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define Inf 1000000000000000

int main(){
	
	int N;
	cin>>N;
	
	vector<int> A(N),B(N);
	
	mf_graph<int> G(2*N+2);
	int S = N*2,T = N*2+1;
	vector<int> a(N),b(N);
	rep(i,N){
		cin>>A[i]>>B[i];
		A[i]--;B[i]--;
		a[i] = G.add_edge(i,N+A[i],1);
		b[i] = G.add_edge(i,N+B[i],1);
		G.add_edge(S,i,1);
		G.add_edge(N+i,T,1);
	}
	
	if(G.flow(S,T)!=N){
		cout<<"No"<<endl;
		return 0;
	}
	cout<<"Yes"<<endl;
	
	vector<int> ans(N);
	rep(i,N){
		if(G.get_edge(a[i]).flow)ans[i] = 0;
		else ans[i] = 1;
	}
	
	rep(i,N){
		if(ans[i]==0)cout<<A[i]+1<<endl;
		else cout<<B[i]+1<<endl;
	}
	
	
	return 0;
}