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#include <unordered_map>
#include <string>
#include <iostream>
using namespace std;
int main()
{
    unordered_map<string, int> degree;
    int n(0);
    string a, b;
    cin>>n;
    for(int i=0; i<n; ++i){
        cin>>a>>b;
        degree[a] += 1;
        degree[b] -= 1;
    }
    for(auto it = degree.begin(); it!=degree.end(); it++){
        if(it->second==-1) b = it->first;
        else if(it->second == 1) a = it->first;
    }
    cout<<a<<' '<<b<<endl;
}
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