Solution: Replace Words

Understand how to solve the Replace Words problem by building a trie from dictionary prefixes and using it to efficiently find and replace the shortest matching prefix in each word of a sentence. This lesson teaches you to optimize searches, improve time complexity, and handle prefix matching using trie data structures.

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Statement
Solution
- Naive approach
- Optimized approach using trie

Statement

In this problem, we are considering the words that are composed of a prefixA prefix is a formative element (the smallest meaningful constituent of a linguistic expression) used at the very beginning of a word. For example, ‘un’, ‘dis’, ‘anti’, etc. and a postfixA postfix is a formative element used at the end of a word.. For example, if we append a postfix “happy” to a prefix “un”, it forms the word “unhappy”. Similarly, “disagree” is formed from a prefix, “dis” followed by a postfix, “agree”.

You’re given a dictionary, dictionary, consisting of prefixes, and a sentence, sentence, which has words separated by spaces only. Your task is to replace the postfix in sentence with their prefixes given in dictionary (if found) and return the modified sentence.

A couple of points to keep in mind:

If a postfix in the sentence matches more than one prefix in the dictionary, replace it with the prefix that has the shortest length. For example, if we have the sentence “iphone is amazing”, and the dictionary ${$ “i”, “ip”, “hone” $}$ , then the word “iphone” has two prefixes in the dictionary “i” and “ip”, but we will replace it with the one that is shorter among the two, that is, “i”.
If there is no root word against any word in the sentence, leave it unchanged.

Constraints:

$1 \leq$ dictionary.length $\leq 1000$
$1 \leq$ dictionary[i].length $\leq 100$
dictionary[i] consists of only lowercase letters.
$1 \leq$ sentence.length $\leq 10^3$

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