Solution: Verifying an Alien Dictionary

Explore how to verify the lexicographical order of words in an alien dictionary using topological sorting. This lesson helps you understand how to efficiently compare adjacent words based on a custom alphabet order, assess character rankings, and implement a solution with optimal time and space complexity.

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Statement
Solution
- Naive approach
- Optimized approach using topological sort

Statement

In an alien language, the alphabet consists of the same lowercase English letters but arranged in a different order.

Given a list of words, words, written in this alien language, and a string order representing the order of the alien alphabet (as a permutation of lowercase letters), return TRUE if the words are sorted lexicographically according to order; otherwise, return FALSE.

Note: A word a is considered lexicographically smaller than word b if:
At the first position where the two words differ, the character in a comes before the character in b in the given order string.
If one word is a prefix of the other (and all compared characters are the same), then the shorter word is considered smaller.