# ---
# title: 1081. Smallest Subsequence of Distinct Characters
# id: problem1081
# author: Tian Jun
# date: 2020-10-31
# difficulty: Medium
# categories: String, Stack, Greedy
# link: <https://leetcode.com/problems/smallest-subsequence-of-distinct-characters/description/>
# hidden: true
# ---
# 
# Return the lexicographically smallest subsequence of `s` that contains all the
# distinct characters of `s` exactly once.
# 
# **Note:** This question is the same as 316:
# <https://leetcode.comhttps://leetcode.com/problems/remove-duplicate-letters/>
# 
# 
# 
# **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.
# 
# 
## @lc code=start
using LeetCode

## add your code here:
## @lc code=end
