Merge pull request #1172 from xiaofei-2020/back04

添加（0216.组合总和III.md）：增加typescript版本

problems/0216.组合总和III.md

@@ -396,6 +396,30 @@ var combinationSum3 = function(k, n) {
 };
 ```
 
+## TypeScript
+
+```typescript
+function combinationSum3(k: number, n: number): number[][] {
+    const resArr: number[][] = [];
+    function backTracking(k: number, n: number, sum: number, startIndex: number, tempArr: number[]): void {
+        if (sum > n) return;
+        if (tempArr.length === k) {
+            if (sum === n) {
+                resArr.push(tempArr.slice());
+            }
+            return;
+        }
+        for (let i = startIndex; i <= 9 - (k - tempArr.length) + 1; i++) {
+            tempArr.push(i);
+            backTracking(k, n, sum + i, i + 1, tempArr);
+            tempArr.pop();
+        }
+    }
+    backTracking(k, n, 0, 1, []);
+    return resArr;
+};
+```
+
 ## C
 
 ```c