1081. Smallest Subsequence of Distinct Characters

https://leetcode.com/problems/smallest-subsequence-of-distinct-characters

Description

Given a string s, return the lexicographically smallest subsequence of s that contains all the distinct characters of s exactly once.

Example 1:

**Input:** s = "bcabc"
**Output:** "abc"

Example 2:

**Input:** s = "cbacdcbc"
**Output:** "acdb"

Constraints:

• 1 <= s.length <= 1000

• s consists of lowercase English letters.

Note: This question is the same as 316: https://leetcode.com/problems/remove-duplicate-letters/

ac