Anagram Checker

QA says "aaz" and "zza" are being reported as anagrams.

isAnagram(a, b) returns true if b uses exactly the same letters as a, the same number of times.

Fix the code so every test passes. Keep the function name isAnagram.

Test cases

• isAnagram("anagram", "nagaram") → true
• isAnagram("rat", "car") → false
• isAnagram("aaz", "zza") → false
• isAnagram("", "") → true

Stuck? Hints go from a nudge to the exact fix.