//|Art|
#pragma GCC optimize("02,unroll-loops")
#pragma GCC target("avx2,fma")
#include <iostream>
#include <chrono>
//#include <bits/stdc++.h>
#define el cout << '\n'
#define fi first
#define se second
#define pb push_back
#define ll long long
#define st string
#define N 600
#define sz(x) (x).size()
#define all(v) (v).begin(), (v).end()
#define FOR(a,b,c) for(int a=b;a<=c;++a)
#define FORE(a,b,c) for(int a=b;a>=c;--a)
#define FED(a,b,c) for(int a=b;a<c;++a)
#define __Art__ signed main()
#define NAME "Art"
using namespace std;
string a[10000];
st p;
int n, m, k, x;
void cal (st s){
if (sz(s) == n) cout << s, el;
else FED (i, 0, k) cal(s + a[sz(s) + 1][i]);
}
void sol(){
n = 3, k = 2;
//a[1] = "ag", a[2] = "iy", a[3] = "ef" ;
st s = "";
FOR (i, 1, m) cin >> s, a[i] = s;
cout << a[1];
//cal(s);
}
__Art__{
if (fopen(NAME".INP", "r")) {
freopen(NAME".INP", "r", stdin);
freopen(NAME".OUT", "w", stdout);
}
/*ios_base::sync_with_stdio(false);
cin.tie(nullptr);
cout.tie(nullptr);*/
int t = 1;
//cin >> t;
while (t--) sol();
cerr << "\nTime elapsed: " << 1.0 * clock() / CLOCKS_PER_SEC << "s\n";
return (0 ^ 0);
}
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