fix(midi): rearrange prompt

Author: jaspwr

competition/midi/prob.md

@@ -32,9 +32,6 @@ given in the following format:
   * `156` (equal to `0x9c` in Base 10), representing turning a note **ON**.
 * `<note>` is an integer between 0 and 127.
 
-* If a note is turned on again while it's already held or turned off while it's already released, that message does nothing.
-* If a note off and on event are sent on the same frame, those notes do not overlap. The note off events are processed first.
-
 For example, in the following, only at most **1** note is being played at any one instant.
 ```text
 0 156 126
@@ -43,6 +40,10 @@ For example, in the following, only at most **1** note is being played at any on
 1000 140 127
 ```
 
+Note that:
+* If a note is turned on again while it's already held or turned off while it's already released, that message does nothing.
+* If a note off and on event are sent on the same frame, those notes do not overlap. The note off events are processed first.
+
 ## Output
 
 Output a single integer, which is the highest number of notes being played at the same time.