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BruteForce, check all pairs and verify if they differ in one character. O(n^2 * m) where n is the number of words and m is the length of each string.
O(m^2 * n), Use hashset, to insert all possible combinations adding a character "*". For example: If dict[i] = "abc", insert ("*bc", "a*c" and "ab*").
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Rolling hash allows efficient recomputation of string hashes when one character position changes. Instead of rebuilding the entire string each time, the hash can be updated quickly, enabling an overall linear-style solution.
Yes, variations of this problem appear in technical interviews at large tech companies. It tests knowledge of hashing, string manipulation, and optimization techniques beyond brute-force comparisons.
The optimal approach uses a hash table combined with a rolling hash technique. By masking each character position and hashing the remaining string, we can detect if another string differs by exactly one character using constant-time hash lookups.
A hash set or hash map works best for this problem. It allows fast storage and lookup of modified string hashes, helping detect matches where two strings differ at exactly one position.