feat: add typescript solution to lc problem: No.0242.Valid Anagram (#526)

Author: zhaocchen

solution/0200-0299/0242.Valid Anagram/README.md

@@ -80,6 +80,21 @@ class Solution {
 }
 ```
 
+### **TypeScript**
+
+```ts
+function isAnagram(s: string, t: string): boolean {
+    if (s.length != t.length) return false;
+    let record = new Array(26).fill(0);
+    let base = 'a'.charCodeAt(0);
+    for (let i = 0; i < s.length; ++i) {
+        ++record[s.charCodeAt(i) - base];
+        --record[t.charCodeAt(i) - base];
+    }
+    return record.every(v => v == 0);
+};
+```
+
 ### **C++**
 
 ```cpp

solution/0200-0299/0242.Valid Anagram/README_EN.md

@@ -72,6 +72,21 @@ class Solution {
 }
 ```
 
+### **TypeScript**
+
+```ts
+function isAnagram(s: string, t: string): boolean {
+    if (s.length != t.length) return false;
+    let record = new Array(26).fill(0);
+    let base = 'a'.charCodeAt(0);
+    for (let i = 0; i < s.length; ++i) {
+        ++record[s.charCodeAt(i) - base];
+        --record[t.charCodeAt(i) - base];
+    }
+    return record.every(v => v == 0);
+};
+```
+
 ### **C++**
 
 ```cpp

solution/0200-0299/0242.Valid Anagram/Solution.ts

@@ -0,0 +1,10 @@
+function isAnagram(s: string, t: string): boolean {
+    if (s.length != t.length) return false;
+    let record = new Array(26).fill(0);
+    let base = 'a'.charCodeAt(0);
+    for (let i = 0; i < s.length; ++i) {
+        ++record[s.charCodeAt(i) - base];
+        --record[t.charCodeAt(i) - base];
+    }
+    return record.every(v => v == 0);
+};