1081: Smallest Subsequence of Distinct Characters

Problem Statement

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/

Code Solution