Solution Implement trie prefix tree

Author: doitduri

implement-trie-prefix-tree/doitduri.swift

@@ -0,0 +1,46 @@
+class TrieNode {
+    var children: [Character: TrieNode] = [:]
+    var isEnd: Bool = false
+}
+
+class Trie {
+    private let root: TrieNode
+    
+    init() {
+        root = TrieNode()
+    }
+    
+    func insert(_ word: String) {
+        var current = root
+        for char in word {
+            if current.children[char] == nil {
+                current.children[char] = TrieNode()
+            }
+            current = current.children[char]!
+        }
+        current.isEnd = true
+    }
+    
+    func search(_ word: String) -> Bool {
+        guard let node = findNode(word) else {
+            return false
+        }
+        return node.isEnd
+    }
+    
+    func startsWith(_ prefix: String) -> Bool {
+        return findNode(prefix) != nil
+    }
+    
+    private func findNode(_ prefix: String) -> TrieNode? {
+        var current = root
+        for char in prefix {
+            guard let next = current.children[char] else {
+                return nil
+            }
+            current = next
+        }
+        return current
+    }
+}
+