#include<iostream>
using namespace std;
int ans = 0;

struct T
{
	int l = -1, r = -1;
	char v = '*';
}node[1000010];

void qxbl(int root)
{
	printf("%c", node[root].v);
	if (node[root].l != -1)
		qxbl(node[root].l);
	if (node[root].r != -1)
		qxbl(node[root].r);
}

int main()
{
	int n;
	cin >> n;
	int ff = 1, aa = 0;
	for (int i = 1; i <= n; i++)
	{
		char root, l, r;
		cin >> root >> l >> r;
		if (ff)
		{
			aa = root - 'a';
			ff = 0;
		}
		node[root - 'a'].v = root;
		if (l != '*')
		{
			node[l - 'a'].v = l;
			node[root - 'a'].l = l - 'a';
		}
		if (r != '*')
		{
			node[r - 'a'].v = r;
			node[root - 'a'].r = r - 'a';
		}
	}
	qxbl(aa);
}