# ---
# title: 76. Minimum Window Substring
# id: problem76
# author: Tian Jun
# date: 2020-10-31
# difficulty: Hard
# categories: Hash Table, Two Pointers, String, Sliding Window
# link: <https://leetcode.com/problems/minimum-window-substring/description/>
# hidden: true
# ---
# 
# Given two strings `s` and `t`, return _the minimum window in`s` which will
# contain all the characters in `t`_. If there is no such window in `s` that
# covers all characters in `t`, return _the empty string`""`_.
# 
# **Note** that If there is such a window, it is guaranteed that there will
# always be only one unique minimum window in `s`.
# 
# 
# 
# **Example 1:**
# 
#     
#     
#     Input: s = "ADOBECODEBANC", t = "ABC"
#     Output: "BANC"
#     
# 
# **Example 2:**
# 
#     
#     
#     Input: s = "a", t = "a"
#     Output: "a"
#     
# 
# 
# 
# **Constraints:**
# 
#   * `1 <= s.length, t.length <= 105`
#   * `s` and `t` consist of English letters.
# 
# 
# 
# **Follow up:** Could you find an algorithm that runs in `O(n)` time?
# 
# 
## @lc code=start
using LeetCode

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