1653. Minimum Deletions to Make String Balanced Medium

1/**
2 * [1653] Minimum Deletions to Make String Balanced
3 *
4 * You are given a string s consisting only of characters 'a' and 'b'​​​​.
5 * You can delete any number of characters in s to make s balanced. s is balanced if there is no pair of indices (i,j) such that i < j and s[i] = 'b' and s[j]= 'a'.
6 * Return the minimum number of deletions needed to make s balanced.
7 *  
8 * Example 1:
9 * 
10 * Input: s = "aababbab"
11 * Output: 2
12 * Explanation: You can either:
13 * Delete the characters at 0-indexed positions 2 and 6 ("aa<u>b</u>abb<u>a</u>b" -> "aaabbb"), or
14 * Delete the characters at 0-indexed positions 3 and 6 ("aab<u>a</u>bb<u>a</u>b" -> "aabbbb").
15 * 
16 * Example 2:
17 * 
18 * Input: s = "bbaaaaabb"
19 * Output: 2
20 * Explanation: The only solution is to delete the first two characters.
21 * 
22 *  
23 * Constraints:
24 * 
25 * 	1 <= s.length <= 10^5
26 * 	s[i] is 'a' or 'b'​​.
27 * 
28 */
29pub struct Solution {}
30
31// problem: https://leetcode.com/problems/minimum-deletions-to-make-string-balanced/
32// discuss: https://leetcode.com/problems/minimum-deletions-to-make-string-balanced/discuss/?currentPage=1&orderBy=most_votes&query=
33
34// submission codes start here
35
36impl Solution {
37    pub fn minimum_deletions(s: String) -> i32 {
38        0
39    }
40}
41
42// submission codes end
43
44#[cfg(test)]
45mod tests {
46    use super::*;
47
48    #[test]
49    fn test_1653() {
50    }
51}
52