Trie (#19)

* Trie for english words

* Added trie for numbers

* Update

Trie_For_Natural_Numbers/Trie.cpp

@@ -0,0 +1,152 @@
+#include <iostream>
+
+using namespace std;
+
+struct node
+{
+    node *number[10];
+    bool isLeaf;
+} *root = NULL;
+
+node *getNode()
+{
+    node *temp = new node();
+    temp -> isLeaf = false;
+
+    for(int i = 0; i < 10; i++)
+    {
+        temp -> number[i] = NULL;
+    }
+
+    return temp;
+}
+
+void insert(int a)
+{
+    if(root == NULL)
+        root = getNode();
+
+    node *current = root;
+
+    while(a != 0)
+    {
+        if(current -> number[a % 10] == NULL)
+        {
+            node *new_node = getNode();
+            current -> number[a % 10] = new_node;
+            current = new_node;
+        }
+        else
+            current = current -> number[a % 10];
+
+        a /= 10;
+    }
+
+    current -> isLeaf = true;
+}
+
+void search(int value)
+{
+    if(root == NULL)
+        cout << "There is no word in Trie" << endl;
+
+    node *current = root;
+    int a = value;
+
+    while(a != 0)
+    {
+        if(current -> number[a % 10] == NULL)
+        {
+            break;
+        }
+        else
+            current = current -> number[a % 10];
+
+        a /= 10;
+    }
+
+    if(a == 0 && current -> isLeaf == true)
+        cout << value << " Found" << endl;
+    else
+        cout << value << " Not Present" << endl;
+}
+
+bool isFreeNode(node *root)
+{
+    for(int i = 0; i < 10; i++)
+    {
+        if(root -> number[i] != NULL)
+            return false;
+    }
+
+    return true;
+}
+
+bool removeNumber(node *root, int a)
+{
+    if(root)
+    {
+        if(a == 0)
+        {
+            if(root -> isLeaf)
+            {
+                root -> isLeaf = false;
+
+                if(isFreeNode(root))
+                    return true;
+            }
+
+            return false;
+        }
+        else
+        {
+            if(removeNumber(root -> number[a % 10], a / 10))
+            {
+                delete root -> number[a % 10];
+                root -> number[a % 10] = NULL;
+
+                return (!root -> isLeaf && isFreeNode(root));
+            }
+        }
+    }
+
+    return false;
+}
+
+void remove(int a)
+{
+    if(a != 0 && root != NULL)
+        removeNumber(root, a);
+}
+
+int main()
+{
+    int a = 99, b = 9999, c = 9987, d = 8687, e = 5499;
+
+    insert(a);
+    insert(b);
+    insert(c);
+    insert(d);
+    insert(e);
+
+    search(a);
+    search(b);
+    search(e);
+    search(7676);
+
+    remove(a);
+
+    search(a);
+
+    return 0;
+}
+
+/* Output
+
+99 Found
+9999 Found
+5499 Found
+7676 Not Present
+99 Not Present
+
+*/

Trie_For_Words/Trie.cpp

@@ -0,0 +1,154 @@
+#include <iostream>
+
+using namespace std;
+
+struct node
+{
+    node *alphabet[26];
+    bool isLeaf;
+} *root = NULL;
+
+node *getNode()
+{
+    node *temp = new node();
+    temp -> isLeaf = false;
+
+    for(int i = 0; i < 26; i++)
+    {
+        temp -> alphabet[i] = NULL;
+    }
+
+    return temp;
+}
+
+void insert(string a)
+{
+    if(root == NULL)
+        root = getNode();
+
+    node *current = root;
+
+    for(unsigned int i = 0; i < a.length(); i++)
+    {
+        a[i] = tolower(a[i]);
+
+        if(current -> alphabet[int(a[i]) - 97] == NULL)
+        {
+            node *new_node = getNode();
+            current -> alphabet[int(a[i]) - 97] = new_node;
+            current = new_node;
+        }
+        else
+            current = current -> alphabet[int(a[i]) - 97];
+    }
+
+    current -> isLeaf = true;
+}
+
+void search(string a)
+{
+    if(root == NULL)
+        cout << "There is no word in Trie" << endl;
+
+    node *current = root;
+    unsigned int i;
+
+    for(i = 0; i < a.length(); i++)
+    {
+        a[i] = tolower(a[i]);
+
+        if(current -> alphabet[int(a[i] - 'a')] == NULL)
+        {
+            break;
+        }
+        else
+            current = current -> alphabet[int(a[i] - 'a')];
+    }
+
+    if(i == a.length() && current -> isLeaf == true)
+        cout << a << " Found" << endl;
+    else
+        cout << a << " Not Present" << endl;
+}
+
+bool isFreeNode(node *root)
+{
+    for(int i = 0; i < 26; i++)
+    {
+        if(root -> alphabet[i] != NULL)
+            return false;
+    }
+
+    return true;
+}
+
+bool removeWord(node *root, string a, unsigned int i)
+{
+    if(root)
+    {
+        if(i == a.length())
+        {
+            if(root -> isLeaf)
+            {
+                root -> isLeaf = false;
+
+                if(isFreeNode(root))
+                    return true;
+            }
+
+            return false;
+        }
+        else
+        {
+            a[i] = tolower(a[i]);
+
+            if(removeWord(root -> alphabet[int(a[i]) - 97], a, i + 1))
+            {
+                delete root -> alphabet[int(a[i]) - 97];
+                root -> alphabet[int(a[i]) - 97] = NULL;
+
+                return (!root -> isLeaf && isFreeNode(root));
+            }
+        }
+    }
+
+    return false;
+}
+
+void remove(string a)
+{
+    if(a.length() && root != NULL)
+        removeWord(root, a, 0);
+}
+
+int main()
+{
+    string a = "aman", b = "akshit", c = "adish", d = "akshay", e = "akash";
+
+    insert(a);
+    insert(b);
+    insert(c);
+    insert(d);
+    insert(e);
+
+    search(a);
+    search(b);
+    search(e);
+    search("swati");
+
+    remove(a);
+
+    search(a);
+
+    return 0;
+}
+
+/* Output
+
+aman Found
+akshit Found
+akash Found
+swati Not Present
+aman Not Present
+
+*/