Update 12.2.md

Author: tcw165

C12-Binary-Search-Trees/12.2.md

@@ -12,7 +12,7 @@ Suppose that we have numbers between 1 and 1000 in a binary search tree and want
 ***If a sequence is a binary search tree, it must have the properties of the binary search tree, so that 's the key to this problem.***
 
 GROUP 3 is impossible,912 > 911
-GROUP 5 is impossible,278 < 299
+GROUP 5 is impossible,347 > 299
 
 ### Exercises 12.2-2
 ***