Problem:
Rooted Trees

A graph G = (V, E) is a data structure where V is a finite set of vertices and E is a binary relation on V represented by a set of edges. Fig. 1 illustrates an example of a graph (or graphs).

Fig. 1

A free tree is a connnected, acyclic, undirected graph. A rooted tree is a free tree in which one of the vertices is distinguished from the others. A vertex of a rooted tree is called "node."

Your task is to write a program which reports the following information for each node u of a given rooted tree T:

node ID of u

parent of u

depth of u

node type (root, internal node or leaf)

a list of chidlren of u

If the last edge on the path from the root r of a tree T to a node x is (p, x), then p is the parent of x, and x is a child of p. The root is the only node in T with no parent.

A node with no children is an external node or leaf. A nonleaf node is an internal node

The number of children of a node x in a rooted tree T is called the degree of x.

The length of the path from the root r to a node x is the depth of x in T.

Here, the given tree consists of n nodes and evey node has a unique ID from 0 to n-1.

Fig. 2 shows an example of rooted trees where ID of each node is indicated by a number in a circle (node). The example corresponds to the first sample input.

Fig. 2

Input

The first line of the input includes an integer n, the number of nodes of the tree.

In the next n lines, the information of each node u is given in the following format:

id k c1 c2 ... ck

where id is the node ID of u, k is the degree of u, c1 ... ck are node IDs of 1st, ... kth child of u. If the node does not have a child, the k is 0.

Output

Print the information of each node in the following format ordered by IDs:

node id: parent = p, depth = d, type, [c1...ck]

p is ID of its parent. If the node does not have a parent, print -1.

d is depth of the node.

type is a type of nodes represented by a string (root, internal node or leaf). If the root can be considered as a leaf or an internal node, print root.

c1...ck is the list of children as a ordered tree.

Please follow the format presented in a sample output below.

Constraints

1 ≤ n ≤ 100000

Sample Input 1

13
0 3 1 4 10
1 2 2 3
2 0
3 0
4 3 5 6 7
5 0
6 0
7 2 8 9
8 0
9 0
10 2 11 12
11 0
12 0

Sample Output 1

node 0: parent = -1, depth = 0, root, [1, 4, 10]
node 1: parent = 0, depth = 1, internal node, [2, 3]
node 2: parent = 1, depth = 2, leaf, []
node 3: parent = 1, depth = 2, leaf, []
node 4: parent = 0, depth = 1, internal node, [5, 6, 7]
node 5: parent = 4, depth = 2, leaf, []
node 6: parent = 4, depth = 2, leaf, []
node 7: parent = 4, depth = 2, internal node, [8, 9]
node 8: parent = 7, depth = 3, leaf, []
node 9: parent = 7, depth = 3, leaf, []
node 10: parent = 0, depth = 1, internal node, [11, 12]
node 11: parent = 10, depth = 2, leaf, []
node 12: parent = 10, depth = 2, leaf, []

Sample Input 2

4
1 3 3 2 0
0 0
3 0
2 0

Sample Output 2

node 0: parent = 1, depth = 1, leaf, []
node 1: parent = -1, depth = 0, root, [3, 2, 0]
node 2: parent = 1, depth = 1, leaf, []
node 3: parent = 1, depth = 1, leaf, []

Note

You can use a left-child, right-sibling representation to implement a tree which has the following data:

the parent of u

the leftmost child of u

the immediate right sibling of u

Reference

Introduction to Algorithms, Thomas H. Cormen, Charles E. Leiserson, Ronald L. Rivest, and Clifford Stein. The MIT Press.

Solution in C# (judge verdict: Accepted)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ALDS1_7_A {
    class Node {
        public int Parent { get; set; }
        public int Depth { get; set; }
        public List<int> Children { get; set; }

        public Node() {
            Parent = -1;
            Children = new List<int>();
        }
    }

    class Program {
        static void Main(string[] args) {
            int n = int.Parse(Console.ReadLine());
            Dictionary<int, Node> nodes = Enumerable.Range(0, n)
                .ToDictionary(i => i, i => new Node());

            for(int i = 0; i < n; i++) {
                string[] input = Console.ReadLine().Split(' ');
                int nodeId = int.Parse(input[0]);
                int childrenVolume = int.Parse(input[1]);
                if (childrenVolume == 0)
                    continue;
                for (int j = 0; j < childrenVolume; j++) {
                    int childId = int.Parse(input[j + 2]);
                    nodes[nodeId].Children.Add(childId);
                    nodes[childId].Parent = nodeId;
                }
            }

            int root = GetParent(nodes);
            CheckDepth(nodes, root);
            Print(nodes);
        }

        static int GetParent(Dictionary<int,Node> nodes) {
            for (int i = 0; i < nodes.Count; i++)
                if (nodes[i].Parent == -1)
                    return i;
            return -1;
        }

        static void CheckDepth(Dictionary<int, Node> nodes,int root) {
            Stack<int> stk = new Stack<int>(nodes[root].Children);

            while (stk.Count > 0) {
                int cur = stk.Pop();
                nodes[cur].Depth = nodes[nodes[cur].Parent].Depth + 1;
                if (nodes[cur].Children.Count != 0) {
                    foreach (var child in nodes[cur].Children) {
                        stk.Push(child);
                    }
                }
            }
        }

        static void Print(Dictionary<int, Node> nodes) {
            StringBuilder sb = new StringBuilder();
            for(int i = 0; i < nodes.Count; i++) {
                sb.Append("node " + i);
                sb.Append(": parent = " + nodes[i].Parent);
                sb.Append(", depth = " + nodes[i].Depth);
                sb.Append(", " + GetType(nodes, i));
                sb.Append(", [");
                for(int j = 0; j < nodes[i].Children.Count; j++) {
                    if (j > 0)
                        sb.Append(", ");
                    sb.Append(nodes[i].Children[j]);
                }
                sb.AppendLine("]");
            }
            Console.Write(sb);
        }

        static string GetType(Dictionary<int,Node>nodes,int index) {
            if (nodes[index].Parent == -1)
                return "root";
            if (nodes[index].Children.Count == 0)
                return "leaf";
            return "internal node";
        }
    }
}