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Concept

Implement Trie Methods

LeetCode #208Medium
insert · search · startsWith
step 1 / 9
trie
•
○ = node · ◎ ringed = end of a word
insert / search / startsWith
▸
1insert(word):
2    cur = root
3    for ch in word: descend, creating if needed
4    cur.isWord = true
5 
6search(word):
7    walk word; node = end
8    return node exists AND node.isWord
9 
10startsWith(prefix):
11    walk prefix; return the path exists
state
  • methodsinsert · search · startsWith

line 1Implement the three Trie methods: insert(word), search(word) — is it a STORED word? — and startsWith(prefix) — does any word start this way? The subtle one is search vs startsWith.