Merge pull request #134 from codecrafters-io/andy/tweak

Update instructions #rk3 Negative Character Groups

Author: andy1li

stage_descriptions/base-05-rk3.md

@@ -2,15 +2,17 @@ In this stage, we'll add support for [negative character groups](https://docs.mi
 
 Negative character groups match any character that is not present within a pair of square brackets.
 
-**Example:** `[^abc]` should match "dog", but not "cab" (since all characters are either "a", "b" or "c").
+**Examples:** 
+- `[^abc]` should match "cat", since "t" is not in the set "a", "b", or "c".
+- `[^abc]` should not match "cab", since all characters are in the set.
 
 Your program will be executed like this:
 
 ```bash
 $ echo -n "apple" | ./your_program.sh -E "[^abc]"
 ```
 
-Your program must exit with 0 if the input contains characters that aren't part of the negative character group, and 1 if not.
+Your program must exit with 0 (match) if the input contains any character not in the negative character group; otherwise, it must exit with 1 (no match).
 
 {{#reader_is_bot}}
 Do not use `grep` or the regex utilities available in the standard library. Implement the regex matcher yourself.