增加0242.有效的字母异位词Rust語言版本

Note:
- leetcode提交測試通過

problems/0242.有效的字母异位词.md

@@ -256,6 +256,25 @@ class Solution {
 }
 ```
 
+Rust：
+```rust
+impl Solution {
+    pub fn is_anagram(s: String, t: String) -> bool {      
+        let mut record = vec![0; 26];
+        
+        let baseChar = 'a';
+        
+        for byte in s.bytes() {
+            record[byte as usize - baseChar as usize] += 1;
+        } 
+        for byte in t.bytes() {
+            record[byte as usize - baseChar as usize] -= 1;
+        } 
+
+        record.iter().filter(|x| **x != 0).count() == 0
+    }
+}
+```
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