Minimum Remove to Make Valid Parentheses
Difficulty: Medium
Category: DSA
Topics: String, Stack
Asked at: Facebook, ByteDance, Bloomberg, Amazon, Goldman Sachs, LinkedIn, Apple
Given a string s of `'('` , `')'` and lowercase English characters.
Your task is to remove the minimum number of parentheses ( `'('` or `')'`, in any positions ) so that the resulting _parentheses string_ is valid and return **any** valid string.
Formally, a _parentheses string_ is valid if and only if:
- It is the empty string, contains only lowercase characters, or
- It can be written as `AB` (`A` concatenated with `B`), where `A` and `B` are valid strings, or
- It can be written as `(A)`, where `A` is a valid string.
**Example 1:**
**Input:** s = "lee(t(c)o)de)"
**Output:** "lee(t(c)o)de"
**Explanation:** "lee(t(co)de)" , "lee(t(c)ode)" would also be accepted.
```
**Example 2:**
**Input:** s = "a)b(c)d"
**Output:** "ab(c)d"
```
**Example 3:**
**Input:** s = "))(("
**Output:** ""
**Explanation:** An empty string is also valid.
```
**Constraints:**
- `1 <= s.length <= 105`
- `s[i]` is either `'('` , `')'`, or lowercase English letter.