#include<bits/stdc++.h>
using namespace std;

int main()
{
	int N; cin>>N;
	vector<string> s(N),t(N);
	for(int i=0;i<N;i++) cin>>s[i]>>t[i];
	
	sort(s.begin(),s.end());
	set<string> used;
	for(int i=0;i<N;i++){
		if(binary_search(s.begin(),s.end(),t[i])) continue;
		if(used.count(t[i])) continue;
		cout<<t[i]<<endl;
		used.insert(t[i]);
	}
	return 0;
}