Update 1002.查找常用字符.md

Add TypeScript solution.

problems/1002.查找常用字符.md

@@ -253,6 +253,41 @@ var commonChars = function (words) {
 	return res
 };
 ```
+
+TypeScript
+```ts
+function commonChars(words: string[]): string[] {
+  let result: string[] = [];
+  if (words.length === 0) return result;
+  const size: number = 26;
+  const hash: number[] = new Array(size).fill(0);
+  const otherHash: number[] = new Array(size).fill(0);
+  let pivot: number = 'a'.charCodeAt(0);
+  // First word
+  for (let character of words[0]) {
+    hash[character.charCodeAt(0) - pivot]++;
+  }
+  // Other words
+  for (let i = 1; i < words.length; i++) {
+    for (let character of words[i]) {
+      otherHash[character.charCodeAt(0) - pivot]++;
+    }
+    // Update the first hash with min
+    for (let j = 0; j < size; j++) {
+      hash[j] = Math.min(hash[j], otherHash[j]);
+    }
+    // Reset otherHash
+    otherHash.fill(0);
+  }
+  // Construct the result
+  hash.forEach((element, index) => {
+    while (element-- > 0) {
+      result.push(String.fromCharCode(index + pivot));
+    }
+  });
+  return result;
+}
+```
 GO
 ```golang
 func commonChars(words []string) []string {