Jun 7

Author: siddydutta

2024-06-June-LeetCoding-Challenge/README.md

@@ -9,7 +9,7 @@
 | June 4 | [409. Longest Palindrome](https://leetcode.com/problems/longest-palindrome/) | Easy | Solved |
 | June 5 | [1002. Find Common Characters](https://leetcode.com/problems/find-common-characters/) | Easy | Solved |
 | June 6 | [846. Hand of Straights](https://leetcode.com/problems/hand-of-straights/) | Medium | Solved |
-| June 7 | []() |  |  |
+| June 7 | [648. Replace Words](https://leetcode.com/problems/replace-words/) | Medium | Solved |
 | June 8 | []() |  |  |
 | June 9 | []() |  |  |
 | June 10 | []() |  |  |
@@ -39,5 +39,5 @@
 | Level  | Problems | Solved | Unsolved |
 | ---    | --- | --- | --- |
 | Easy   | 4 | 4 | 0 |
-| Medium | 2 | 2 | 0 |
+| Medium | 3 | 3 | 0 |
 | Hard   | 0 | 0 | 0 |

2024-06-June-LeetCoding-Challenge/Replace Words.py

@@ -0,0 +1,55 @@
+from typing import List
+
+
+class Node:
+    def __init__(self):
+        self.children = dict()
+        self.is_word = False
+
+
+class Trie:
+    def __init__(self):
+        self.root = Node()
+
+    def insert(self, word: str) -> None:
+        node = self.root
+        for ch in word:
+            node = node.children.setdefault(ch, Node())
+        node.is_word = True
+
+    def shortest_prefix(self, word) -> str:
+        node = self.root
+        prefix = str()
+        for ch in word:
+            if ch not in node.children:
+                return word
+            node = node.children[ch]
+            prefix += ch
+            if node.is_word:
+                return prefix
+        return word
+
+
+class Solution:
+    def replaceWords(self, dictionary: List[str], sentence: str) -> str:
+        trie = Trie()
+        for root in dictionary:
+            trie.insert(root)
+
+        sentence = sentence.split()
+        sentence = map(trie.shortest_prefix, sentence)
+        return ' '.join(sentence)
+
+
+def main():
+    dictionary = ['cat', 'bat', 'rat']
+    sentence = 'the cattle was rattled by the battery'
+    assert Solution().replaceWords(dictionary, sentence) == 'the cat was rat by the bat'  # noqa: E501
+
+    dictionary = ['a', 'b', 'c']
+    sentence = 'aadsfasf absbs bbab cadsfafs'
+    assert Solution().replaceWords(dictionary, sentence) == 'a a b c'
+
+
+if __name__ == '__main__':
+    main()