Given two strings s and t, return true if t is an anagram of s, and false otherwise.

An Anagram is a word or phrase formed by rearranging the letters of a different word or phrase, typically using all the original letters exactly once.

  Example 1: Input: s = "anagram", t = "nagaram" Output: true Example 2: Input: s = "rat", t = "car" Output: false

  Constraints:

1 <= s.length, t.length <= 5 * 10⁴
s and t consist of lowercase English letters.

  Follow up: What if the inputs contain Unicode characters? How would you adapt your solution to such a case?