2124. Check if All A's Appears Before All B's

Given a string `s` consisting of only the characters `'a'` and `'b'`, return `true` if every `'a'` appears before every `'b'` in the string. Otherwise, return `false`.

Example 1:

```Input: s = "aaabbb"
Output: true
Explanation:
The 'a's are at indices 0, 1, and 2, while the 'b's are at indices 3, 4, and 5.
Hence, every 'a' appears before every 'b' and we return true.
```

Example 2:

```Input: s = "abab"
Output: false
Explanation:
There is an 'a' at index 2 and a 'b' at index 1.
Hence, not every 'a' appears before every 'b' and we return false.
```

Example 3:

```Input: s = "bbb"
Output: true
Explanation:
There are no 'a's, hence, every 'a' appears before every 'b' and we return true.
```

Constraints:

• `1 <= s.length <= 100`
• `s[i]` is either `'a'` or `'b'`.

2124. Check if All A's Appears Before All B's
``````struct Solution;

impl Solution {
fn check_string(s: String) -> bool {
let s: Vec<char> = s.chars().collect();
let mut t = s.clone();
t.sort_unstable();
s == t
}
}

#[test]
fn test() {
let s = "aaabbb".to_string();
let res = true;
assert_eq!(Solution::check_string(s), res);
let s = "abab".to_string();
let res = false;
assert_eq!(Solution::check_string(s), res);
let s = "bbb".to_string();
let res = true;
assert_eq!(Solution::check_string(s), res);
}
``````