Check String Permutation | Dataford Interview Questions

Shelf Engine processes text identifiers and needs to verify whether two strings contain exactly the same characters with the same frequencies. Given two strings, determine whether one is a permutation of the other.

The comparison is case-sensitive, and every character counts, including spaces and punctuation. The order of characters does not matter.

Formal Specification

Implement a function that accepts two strings, first and second, and returns a boolean:

Return True if second is a permutation of first.
Return False otherwise.

You may use Python's standard library, but do not modify either input string.

Constraints

0 <= len(first), len(second) <= 10^5
Inputs may contain Unicode characters, whitespace, and punctuation
Character comparison is case-sensitive
A solution should run in O(n) time

Function Signature

def are_permutations(first, second):

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