Check Anagrams with Frequency Arrays

Summary

Determine whether two strings are anagrams by comparing character counts.

Problem statement

Given two strings s and t, return True if t is an anagram of s. Consider all characters exactly as given (case-sensitive). Spaces and punctuation count as characters. Return False otherwise. Both inputs may be empty strings. Time complexity should be O(n).

Task

Implement a function that returns True if two input strings contain the exact same characters with the same frequencies (case-sensitive, includes spaces and punctuation).

Examples

Input format

Two string arguments: is_anagram(s, t)

Output format

Return a boolean: True if t is an anagram of s, otherwise False.

Constraints

0 <= len(s), len(t) <= 10^5. Use O(n) time and O(k) additional space where k is alphabet size.

Samples