Tries

import java.util.ArrayList; 
 
public class TrieNode { 
 
    char letter; 
    int value; 
    TrieNode parent = null; 
    ArrayList<TrieNode> children = new ArrayList<TrieNode>(); 
 
    public TrieNode(char c, int v) { 
        letter = c; 
        value = v; 
    } 
 
    void addString(String s, int y) { 
        System.out.print("Adding String " + "\"" + s + "\"..."); 
        System.out.println(); 
        System.out.println(); 
        TrieNode n = this; 
        boolean noMoreMatching = false; 
        while (!noMoreMatching) { 
            int i; 
            int childrenSize = n.children.size(); 
            for (i = 0; i < n.children.size(); i++) { 
                if (n.children.get(i).letter == s.charAt(0)) { 
                    n = n.children.get(i); 
                    s = s.substring(1, s.length()); 
                    break; 
                } 
            } 
            if (i == childrenSize) { 
                noMoreMatching = true; 
            } 
        } 
        if (s.length() > 0) { 
            addRemainingString(n, s, y); 
        } 
        printTrie(); 
    } 
 
    void addRemainingString(TrieNode n, String s, int y) { 
        for (int i = 0; i < s.length() - 1; i++) { 
            TrieNode m = n.addChild(s.charAt(i), 0); 
            n = m; 
        } 
        n.addChild(s.charAt(s.length() - 1), y); 
    } 
 
    TrieNode addChild(char c, int v) { 
        TrieNode child = new TrieNode(c, v); 
        children.add(child); 
        child.setParent(this); 
        return child; 
    } 
 
    void setParent(TrieNode newParent) { 
        parent = newParent; 
    } 
 
    void printTrie() { 
        TrieNode n = this; 
        printSubTree(n, 0); 
        System.out.println(); 
    } 
 
    int printSubTree(TrieNode n, int level) { 
        for (int a = 0; a < level; a++) { 
            System.out.print("---"); 
        } 
        System.out.print(n.letter); 
        if (n.value != 0) { 
            System.out.print(" " + n.value); 
        } 
        System.out.println(); 
        if (n.children.size() == 0) { 
            return n.letter; 
        } 
        int size = n.children.size(); 
        level++; 
        for (int i = 0; i < size; i++) { 
            printSubTree(n.children.get(i), level); 
        } 
        return -1; 
    } 
 
}

public class ImplementTrie { 
 
    public static void main(String[] args) { 
 
        System.out.println("Initializing Trie"); 
        TrieNode trie = createTrie(); 
 
        trie.printTrie(); 
 
        trie.addString("as", 2); 
        trie.addString("assign", 8); 
        trie.addString("chocolate", 6); 
        trie.addString("nat", 7); 
        trie.addString("assignment", 5); 
        trie.addString("nation", 3); 
        trie.addString("national", 1); 
        trie.addString("assignments", 9); 
 
    } 
 
    public static TrieNode createTrie() { 
        TrieNode root = new TrieNode('.', 0); 
        return root; 
    } 
 
}

using System; 
using System.Collections.Generic; 
 
public class TrieNode 
{ 
    char letter; 
    int value; 
    TrieNode parent = null; 
    List<TrieNode> children = new List<TrieNode>(); 
 
    public TrieNode(char c, int v) 
    { 
        letter = c; 
        value = v; 
    } 
 
    public void addString(String s, int y) 
    { 
        Console.Write("Adding String " + "\"" + s + "\"..."); 
        Console.WriteLine(); 
        Console.WriteLine(); 
        TrieNode n = this; 
        Boolean noMoreMatching = false; 
        while (!noMoreMatching) 
        { 
            int i; 
            int childrenSize = n.children.Count; 
            for (i = 0; i < n.children.Count; i++) 
            { 
                if (n.children[i].letter == s[0]) 
                { 
                    n = n.children[i]; 
                    s = s.Substring(1, s.Length - 1); 
                    break; 
                } 
            } 
            if (i == childrenSize) 
            { 
                noMoreMatching = true; 
            } 
        } 
        if (s.Length > 0) 
        { 
            addRemainingString(n, s, y); 
        } 
        printTrie(); 
    } 
 
    public void addRemainingString(TrieNode n, String s, int y) 
    { 
        for (int i = 0; i < s.Length - 1; i++) 
        { 
            TrieNode m = n.addChild(s[i], 0); 
            n = m; 
        } 
        n.addChild(s[s.Length - 1], y); 
    } 
 
    public TrieNode addChild(char c, int v) 
    { 
        TrieNode child = new TrieNode(c, v); 
        children.Add(child); 
        child.setParent(this); 
        return child; 
    } 
 
    public void setParent(TrieNode newParent) 
    { 
        parent = newParent; 
    } 
 
    public void printTrie() 
    { 
        TrieNode n = this; 
        printSubTree(n, 0); 
        Console.WriteLine(); 
    } 
 
    public int printSubTree(TrieNode n, int level) 
    { 
        for (int a = 0; a < level; a++) 
        { 
            Console.Write("---"); 
        } 
        Console.Write(n.letter); 
        if (n.value != 0) 
        { 
            Console.Write(" " + n.value); 
        } 
        Console.WriteLine(); 
        if (n.children.Count == 0) 
        { 
            return n.letter; 
        } 
        int size = n.children.Count; 
        level++; 
        for (int i = 0; i < size; i++) 
        { 
            printSubTree(n.children[i], level); 
        } 
        return -1; 
    } 
} 

using System; 
 
public class ImplementTrie 
{ 
    public static void Main() 
    { 
        Console.WriteLine("Initializing Trie"); 
        TrieNode trie = createTrie(); 
 
        trie.printTrie(); 
 
        trie.addString("as", 2); 
        trie.addString("assign", 8); 
        trie.addString("chocolate", 6); 
        trie.addString("nat", 7); 
        trie.addString("assignment", 5); 
        trie.addString("nation", 3); 
        trie.addString("national", 1); 
        trie.addString("assignments", 9); 
    } 
 
    public static TrieNode createTrie() 
    { 
        TrieNode root = new TrieNode('.', 0); 
        return root; 
    } 
} 

Initializing Trie
.

Adding String "as"...

.
---a
------s 2

Adding String "assign"...

.
---a
------s 2
---------s
------------i
---------------g
------------------n 8

Adding String "chocolate"...

.
---a
------s 2
---------s
------------i
---------------g
------------------n 8
---c
------h
---------o
------------c
---------------o
------------------l
---------------------a
------------------------t
---------------------------e 6

Adding String "nat"...

.
---a
------s 2
---------s
------------i
---------------g
------------------n 8
---c
------h
---------o
------------c
---------------o
------------------l
---------------------a
------------------------t
---------------------------e 6
---n
------a
---------t 7

Adding String "assignment"...

.
---a
------s 2
---------s
------------i
---------------g
------------------n 8
---------------------m
------------------------e
---------------------------n
------------------------------t 5
---c
------h
---------o
------------c
---------------o
------------------l
---------------------a
------------------------t
---------------------------e 6
---n
------a
---------t 7

Adding String "nation"...

.
---a
------s 2
---------s
------------i
---------------g
------------------n 8
---------------------m
------------------------e
---------------------------n
------------------------------t 5
---c
------h
---------o
------------c
---------------o
------------------l
---------------------a
------------------------t
---------------------------e 6
---n
------a
---------t 7
------------i
---------------o
------------------n 3

Adding String "national"...

.
---a
------s 2
---------s
------------i
---------------g
------------------n 8
---------------------m
------------------------e
---------------------------n
------------------------------t 5
---c
------h
---------o
------------c
---------------o
------------------l
---------------------a
------------------------t
---------------------------e 6
---n
------a
---------t 7
------------i
---------------o
------------------n 3
---------------------a
------------------------l 1

Adding String "assignments"...

.
---a
------s 2
---------s
------------i
---------------g
------------------n 8
---------------------m
------------------------e
---------------------------n
------------------------------t 5
---------------------------------s 9
---c
------h
---------o
------------c
---------------o
------------------l
---------------------a
------------------------t
---------------------------e 6
---n
------a
---------t 7
------------i
---------------o
------------------n 3
---------------------a
------------------------l 1