1614.MaximumNestingDepthoftheParentheses.py

"""
    A string is a valid parentheses string (denoted VPS) if it meets one of the 
    following:
        - It is an empty string "", or a single character not equal to "(" or 
          ")",
        - It can be written as AB (A concatenated with B), where A and B are 
          VPS's, or
        - It can be written as (A), where A is a VPS.

    We can similarly define the nesting depth depth(S) of any VPS S as follows:
        - depth("") = 0
        - depth(C) = 0, where C is a string with a single character not equal 
          to "(" or ")".
        - depth(A + B) = max(depth(A), depth(B)), where A and B are VPS's.
        - depth("(" + A + ")") = 1 + depth(A), where A is a VPS.

    For example, "", "()()", and "()(()())" are VPS's (with nesting depths 0, 
    1, and 2), and ")(" and "(()" are not VPS's.

    Given a VPS represented as string s, return the nesting depth of s.

    Example:
    Input: s = "(1+(2*3)+((8)/4))+1"
    Output: 3
    Explanation: Digit 8 is inside of 3 nested parentheses in the string.

    Example:
    Input: s = "(1)+((2))+(((3)))"
    Output: 3

    Example:
    Input: s = "1+(2*3)/(2-1)"
    Output: 1

    Example:
    Input: s = "1"
    Output: 0

    Constraints:
        - 1 <= s.length <= 100
        - s consists of digits 0-9 and characters '+', '-', '*', '/', '(', 
          and ')'.
        - It is guaranteed that parentheses expression s is a VPS.
"""
#Difficulty: Easy
#167 / 167 test cases passed.
#Runtime: 20 ms
#Memory Usage: 14.1 MB

#Runtime: 20 ms, faster than 99.08% of Python3 online submissions for Maximum Nesting Depth of the Parentheses.
#Memory Usage: 14.1 MB, less than 100.00% of Python3 online submissions for Maximum Nesting Depth of the Parentheses.

class Solution:
    def maxDepth(self, s: str) -> int:
        count = 0
        depth = 0
        for char in s:
            if char == '(':
                count += 1
            if char == ')':
                count -= 1
            depth = max(depth, count)
        return depth