Valid Anagram @Leetcode

Valid Anagram Total Accepted: 16056 Total Submissions: 47146 My Submissions Question Solution
Given two strings s and t, write a function to determine if t is an anagram of s.

For example,
s = "anagram", t = "nagaram", return true.
s = "rat", t = "car", return false.

Note:
You may assume the string contains only lowercase alphabets.

很弱的题。空间和时间的balance.
省空间，用sort.
省时间，用hashtable.