CODE EXAMPLE FOR PYTHON

Valid Parentheses

class Solution:
    def isValid(self, s):
        if s == "":
            return True
        if len(s) < 2:
            return False

        pair_brkts = {
            "{" : "}",
            "(" : ")",
            "[" : "]"
            }
        stack = []

        for i in s:
            if i in pair_brkts:
                stack.append(i)                                #stack i(forward facing brackets) that also exists as keys in our pair_brkts dictionary)
                #print("forward facing brackets", stack)       #to see the contents of your stacked list 
            else:
                if len(stack) == 0 or pair_brkts[stack.pop()] != i:   #if stack list is empty or the value pair of last 
                                                                        #list item isnt same, return False, otherwise break out of loop
                    #print("backward facing brackets", stack)        #print to see whats left of your list after 
                                                                    #looping is over for all your i(i.e brackets)
                    return False
        if len(stack) > 0:                                          #if stack list is not empty at this point, return False, else return True
            return False
        return True

 
        

Task = Solution()
print("1. ", Task.isValid("({[()]})"))
print("2. ", Task.isValid("()[]{}"))
print("3. ", Task.isValid("(]"))