leetcode242

 

                                   242. Valid Anagram

Description：

Given two strings s and t , write a function to determine if t is an anagram of s.

Example 1:

Input: s = "anagram", t = "nagaram"
Output: true

Example 2:

Input: s = "rat", t = "car"
Output: 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?

思路一：将两个字符串排序后判断是否为相同

代码：

class Solution {
public:
    bool isAnagram(string s, string t) {
        sort(s.begin(), s.end());
        sort(t.begin(), t.end());
        return s == t;
    }
};

思路二：定义两个长度26整型数组，下标为0-26(a-z)，存储字符串中出现的字母个数，最后判断是否有不相等个数字母。

代码：

class Solution {
public:
    bool isAnagram(string s, string t) {
        if(s.length() != t.length()) return false;
        vector <int> sArr(26, 0);
        vector <int> tArr(26, 0);
        for(int i = 0; i < s.length(); i++) {
            sArr[s[i] - 'a']++;
            tArr[t[i] - 'a']++;
        }
        for (int i = 0; i < 26; i++) {
            if (sArr[i] != tArr[i])
                return false;
        }
        return true;
    }
};