leetcode解题之242# Valid Anagram Java版 （判断两个字母串是否具有相同的字母组合）

242. Valid Anagram

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

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

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

排序之后是否相等

import java.util.Arrays;
public class Solution {
	public boolean isAnagram(String s, String t) {
		char[] sArr = s.toCharArray();
		char[] tArr = t.toCharArray();

		Arrays.sort(sArr);
		Arrays.sort(tArr);

		return String.valueOf(sArr).equals(String.valueOf(tArr));
	}
}

才用map，若map中含有此key，则value+1；否则 value置1，取的时候最后看是否为0，如果存在不为0的value，返回false

import java.util.HashMap;
import java.util.Map;

public class Solution {
	public boolean isAnagram(String s, String t) {
		//长度不相等，返回false
		if (s.length() != t.length())
			return false;
		//key为出现的字母，value为字母出现的次数
		Map map = new HashMap<>();
		for (int i = 0; i < s.length(); i++) {
			if (map.containsKey(s.charAt(i))) {
				map.put(s.charAt(i), map.get(s.charAt(i)) + 1);
			} else
				map.put(s.charAt(i), 1);
		}
		for (int i = 0; i < t.length(); i++) {
			if (map.containsKey(t.charAt(i))) {
				map.put(t.charAt(i), map.get(t.charAt(i)) - 1);
			} else
				return false;
		}
		for (int i = 0; i < s.length(); i++) {
			if (map.get(s.charAt(i)) != 0)
				return false;

		}
		return true;
	}
}