Implement Trie Prefix Tree solution

Author: PDKhan

implement-trie-prefix-tree/PDKhan.cpp

@@ -0,0 +1,67 @@
+class TrieNode{
+    public:
+        TrieNode* children[26];
+        bool isEnd;
+    
+        TrieNode() {
+            isEnd = false;
+    
+            for(int i = 0; i < 26; i++)
+                children[i] = nullptr;
+        }
+    };
+    
+    class Trie {
+    public:
+        TrieNode* root;
+    
+        Trie() {
+            root = new TrieNode();
+        }
+        
+        void insert(string word) {
+            TrieNode* node = root;
+    
+            for(char ch : word){
+                int index = ch - 'a';
+    
+                if(node->children[index] == nullptr){
+                    node->children[index] = new TrieNode();
+                }
+    
+                node = node->children[index];
+            }
+    
+            node->isEnd = true;
+        }
+        
+        bool search(string word) {        
+            TrieNode* node = root;
+    
+            for(char ch : word){
+                int index = ch - 'a';
+    
+                if(node->children[index] == nullptr)
+                    return false;
+                
+                node = node->children[index];
+            }
+    
+            return node->isEnd;
+        }
+        
+        bool startsWith(string prefix) {
+            TrieNode* node = root;
+    
+            for(char ch : prefix){
+                int index = ch - 'a';
+    
+                if(node->children[index] == nullptr)
+                    return false;
+                
+                node = node->children[index];
+            }
+    
+            return true;
+        }
+    };