第四周作业#015

Week_04/id_15/LeetCode_208_015.py

@@ -0,0 +1,54 @@
+#Data Node to hold char data
+class Node:
+    def __init__(self, val, isWord=False):
+        self.val = val
+        self.child = {}
+        self.isWord = isWord
+
+class Trie:
+
+    def __init__(self):
+        """
+        Initialize your data structure here.
+        """
+        self.root = Node("")
+
+
+    def insert(self, word: str) -> None:
+        """
+        Inserts a word into the trie.
+        """
+        curr = self.root
+        for ch in word:
+            if ch not in curr.child:
+                curr.child[ch] = Node(ch)
+            curr = curr.child.get(ch)
+
+        curr.isWord = True
+
+
+    def search(self, word: str) -> bool:
+        """
+        Returns if the word is in the trie.
+        """
+        curr = self.root
+        for ch in word:
+            if ch in curr.child:
+                curr = curr.child.get(ch)
+            else:
+                return False
+
+        return curr.isWord
+
+    def startsWith(self, prefix: str) -> bool:
+        """
+        Returns if there is any word in the trie that starts with the given prefix.
+        """
+        curr = self.root
+        for ch in prefix:
+            if ch in curr.child:
+                curr = curr.child.get(ch)
+            else:
+                return False
+
+        return True

Week_04/id_15/LeetCode_211_015.py

@@ -0,0 +1,13 @@
+class WordDictionary(object):
+    def __init__(self):
+        self.len2words = collections.defaultdict(list) 
+
+    def addWord(self, word):
+        self.len2words[len(word)].append(word)
+
+    def search(self, word):
+        words = self.len2words[len(word)]
+        for i, char in enumerate(word):
+            words = [w for w in words if char in ('.', w[i])]
+            if not words: return False
+        return True

Week_04/id_15/NOTE.md

@@ -1 +1,8 @@
 # 学习笔记
+
+## 日常计划
+ - 完成相对应的算法习题
+ - 规划长期算法成长路线
+
+## 下周计划
+ - 争取通过算法考试