#268: description update

Author: vetalapo

c-sharp/Problems/bit-manipulation/MissingNumber.cs

@@ -31,11 +31,12 @@
  *
  * Constraints:
  *   • n == nums.length
- *   • 1 <= n <= 104
+ *   • 1 <= n <= 10^4
  *   • 0 <= nums[i] <= n
  *   • All the numbers of nums are unique.
  *
- * Follow up: Could you implement a solution using only O(1) extra space complexity and O(n) runtime complexity?
+ * Follow up:
+ *   Could you implement a solution using only O(1) extra space complexity and O(n) runtime complexity?
  **
  * https://leetcode.com/problems/missing-number/
 ***/