Update 0001.两数之和.md

Add a break statement to break the for-loop in the Typescript solution.

problems/0001.两数之和.md

@@ -349,6 +349,7 @@ function twoSum(nums: number[], target: number): number[] {
         index = helperMap.get(target - nums[i]);
         if (index !== undefined) {
             resArr = [i, index];
+            break;
         }
         helperMap.set(nums[i], i);
     }