#1081

Smallest Subsequence of Distinct Characters

medium · verified · 63.1% accepted · 2,756 likes · top 65%

string · stack · greedy · monotonic stack

⊣ practice⊣ open on leetcode ↗

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"

Solution