#include <iostream>
#include <unordered_set>
#include <unordered_map>
#include <vector>
using namespace std;
 
struct Node {
	int val;
	unordered_map<Node*, int> edges;
	Node(int val): val(val) {}
	void addEdge(Node* node, int weight = 1) {
		edges[node] = weight;
	}
};
 
void dfs_helper(Node* node, unordered_set<Node*> &visiting, unordered_set<Node*> &visited){
	if(!node || visiting.find(node)!=visiting.end())	return;
	if(visited.find(node)!=visited.end()){
		cout<<"Not exploring again: "<<node->val<<endl;
		return;
	}
	visited.insert(node);
	visiting.insert(node);
	cout<<"Visiting: "<<node->val<<endl;
	for(auto p: node->edges){
		dfs_helper(p.first, visiting, visited);
	}
	cout<<"Leaving: "<<node->val<<endl;
	visiting.erase(node);
}
 
void dfs(Node* root){
	unordered_set<Node*> visiting;
	unordered_set<Node*> visited;
	dfs_helper(root, visiting, visited);
	return;
}
 
unordered_map<int, Node*> generate_graph(vector<pair<int,int>> &edges){
	unordered_map<int, Node*> graph;
	int i,j;
	for(auto p: edges){
		i = p.first;
		j = p.second;
		if(graph.find(i)==graph.end())	graph[i] = new Node(i);
		if(graph.find(j)==graph.end())	graph[j] = new Node(j);
		graph[i]->addEdge(graph[j]);
		graph[j]->addEdge(graph[i]);
	}
	return graph;
}
int main() {
	int t;
	int a, b;
	cin>>t;
	vector<pair<int,int>> v;
	while(t--){
		cin>>a>>b;
		v.push_back({a,b});
	}
	unordered_map<int, Node*> graph = generate_graph(v);
	dfs(graph.begin()->second);
	return 0;
}

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