# LeetCode242. Valid Anagram（模拟）

## LeetCode242. Valid Anagram（模拟）

• Easy
• Accepted：295,264
• Submissions：582,802

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.

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

### 链接

https://leetcode.com/problems/valid-anagram/

### 题解

• 排序后判断是否相同，时间复杂度$O(nlogn + mlogm)$
• 用个cnt计数数组记录一遍然后开始匹配，具体看代码，时间复杂度$O(n + m)$

### 代码

• Runtime: 12 ms, faster than 96.12% of C++ online submissions for Valid Anagram.
• Memory Usage: 9 MB, less than 100.00% of C++ online submissions for Valid Anagram.
class Solution {
public:
bool isAnagram(string s, string t) {
int n = s.length(), m = t.length();
int tot = n;
int cnt[256] = {0};
for (int i = 0; i < n; ++i)
cnt[s[i]]++;
for (int i = 0; i < m; ++i)
{
if (cnt[t[i]]-- > 0)
--tot;
// else return 0;
}
return tot == 0 && n == m; // 需要判断是否相等，"a" / "ab"
}
};

The end.
2019年2月14日 星期四