Given two equal-size strings s and t. In one step you can choose any character of t and replace it with another character. Return the minimum number of steps to make t an anagram of s. An Anagram of a string is a string that contains the same characters with a different (or the same) ordering. Example 1: Input: s = "bab", t = "aba" Output: 1 Explanation: Replace the first 'a' in t with b, t = "bba" which is anagram of s. Example 2: Input: s = "leetcode", t = "practice" Output: 5 Explanation: Replace 'p', 'r', 'a', 'i' and 'c' from t with proper characters to make t anagram of s. Example 3: Input: s = "anagram", t = "mangaar" Output: 0 Explanation: "anagram" and "mangaar" are anagrams. Example 4: Input: s = "xxyyzz", t = "xxyyzz" Output: 0 Example 5: Input: s = "friend", t = "family" Output: 4 Constraints: 1 <= s.length <= 50000 s.length == t.length s and t contain lower-case English letters only.