11.11

#include <iostream>
#include <unordered_map>
using namespace std;

unordered_map<char, pair<char, char>> tree; 

void preorder(char node) {
    if (node == '.') return;
    cout << node;               
    preorder(tree[node].first);  
    preorder(tree[node].second); 
}

// 중위 순회 (Inorder Traversal)
void inorder(char node) {
    if (node == '.') return;
    inorder(tree[node].first);   
    cout << node;               
    inorder(tree[node].second);  
}


void postorder(char node) {
    if (node == '.') return;
    postorder(tree[node].first); 
    postorder(tree[node].second);
    cout << node;             
}

int main() {
    int n;
    cin >> n; 

    for (int i = 0; i < n; i++) {
        char node, left, right;
        cin >> node >> left >> right;
        tree[node] = {left, right};
    } 

    // 순회 결과 출력
    preorder('A');  
    cout << endl;
    inorder('A');   
    cout << endl;
    postorder('A'); 
    cout << endl;

    return 0;
}