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MediumPro challengePythonJavaScriptTypeScript

Trie (Prefix Tree)

Data StructuresStrings

Implement a Trie class:

  • insert(word) — add a word.
  • search(word) — return true if the exact word exists.
  • startsWith(prefix) — return true if any word starts with prefix.

solve(ops) replays operations and returns results for search/startsWith.

Sample tests

Test #1Search in empty trie
Input: [[["search","hello"]]]
Output: [false]
Test #2Classic trie sequence from LeetCode 208
Input: [[["insert","apple"],["search","apple"],["search","app"],["startsWith","app"],["insert","app"],["search","app"]]]
Output: [null,true,false,true,null,true]
Test #3Prefix checks
Input: [[["insert","hi"],["startsWith","h"],["startsWith","hi"],["startsWith","hit"]]]
Output: [null,true,true,false]
Test #4Shorter word is a prefix of longer word
Input: [[["insert","a"],["insert","ab"],["search","a"],["search","ab"],["search","abc"]]]
Output: [null,null,true,true,false]
Test #5Two words with shared prefix
Input: [[["insert","cat"],["insert","car"],["search","car"],["search","can"],["startsWith","ca"]]]
Output: [null,null,true,false,true]
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