Solution: Find the Length of the Longest Common Prefix
Explore how to solve the longest common prefix problem between two arrays of positive integers by leveraging hash maps. Learn to precompute numeric prefixes, optimize prefix lookups, and achieve an efficient solution with O((n + m) * d) time complexity. This lesson equips you to implement and understand essential coding interview patterns involving prefix matching and hash sets.
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Statement
You are given two arrays of positive integers, arr1 and arr2.
A prefix of a positive integer is an integer formed by one or more of its digits, beginning from its leftmost digit. For example, 123 is a prefix of 12345, whereas 234 is not.
A common prefix of two integers a and b is an integer c that is simultaneously a prefix of both a and b. For example, 5655359 and 56554 share common prefixes 565 and 5655, while 1223 and 43456 share none.
For every pair (x, y) where x belongs to arr1 and y belongs to arr2, determine the length of the longest common prefix shared between them.
Return the length of the longest common prefix across all such pairs. If no common prefix exists for any pair, return
Note: Common prefixes between elements within the same array do not count.
Constraints:
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