Implement Trie Solution

Author: jinbeom

implement-trie-prefix-tree/kayden.py

@@ -0,0 +1,40 @@
+class Node:
+
+    def __init__(self, ending=False):
+        self.children = {}
+        self.ending = ending
+
+# 공간복잡도: O(w*l) w: 단어 수 l: 단어의 평균 길이
+class Trie:
+
+    def __init__(self):
+        self.head = Node(ending=True)
+
+    # 시간복잡도: O(N)
+    def insert(self, word: str) -> None:
+        node = self.head
+        for ch in word:
+            if ch not in node.children:
+                node.children.setdefault(ch, Node())
+            node = node.children[ch]
+        node.ending = True
+
+    # 시간복잡도: O(N)
+    def search(self, word: str) -> bool:
+        node = self.head
+        for ch in word:
+            if ch not in node.children:
+                return False
+            node = node.children[ch]
+
+        return node.ending
+
+    # 시간복잡도: O(N)
+    def startsWith(self, prefix: str) -> bool:
+        node = self.head
+        for ch in prefix:
+            if ch not in node.children:
+                return False
+            node = node.children[ch]
+
+        return True