Update 034._Search for a Range.md

docs/Leetcode_Solutions/034._Search for a Range.md

@@ -84,7 +84,8 @@ class Solution(object):
             if nums[mid] > target:
                 r = mid - 1
             else:
-                l = mid + 1       
+                l = mid + 1 
+        # 这里直接返回res是因为前面如果判断左边界没返回的话就说明我们判断右边界的时候一定会append元素
         return res
 ```