Python Data Structures

Python :Data Structure in Python:-
Stack Implementation:

class stack:
    def __init__(self):
        self.item = []

    def push(self, val):
        self.item.append(val)

    def pop(self):
        return self.item.pop(0)

    def isempty(self):
        return self.item==[]

    def peek(self):
        return self.item[0]

    def size(self):
        return len(self.item)

• Application of Stack :

class stack:
    def __init__(self):
        self.item = []

    def push(self, val):
        self.item.append(val)

    def pop(self):
        return self.item.pop(0)

    def isempty(self):
        return self.item==[]

    def peek(self):
        return self.item[0]

    def size(self):
        return len(self.item)




def parChecker(input_string):
    x= stack()
    balance = True
    index = 0
    while index < len(input_string) and balance:
        symbol = input_string[index]
        if symbol in "([{":
            x.push(symbol)
        else:
            if(x.isempty()):
                balance =False
            else:
                data = x.pop()
                if not match(data,symbol):
                    balance = False
        index = index + 1

    if(balance and x.isempty()):
        return True
    else :
        return False

def match(open,close):
    open1= "({["
    close1 = ")}]"
    return  open1.index(open) == close1.index(close)


print(parChecker('{{([][])}()}'))

• Application of Stack

def divide(num,base):
    rem_stack =  stack()

    while (num > 0):
        rem = num % base
        rem_stack.push(rem)
        num = num // base

    binstrng = ""
    while not rem_stack.isempty():
        binstrng = binstrng + str(rem_stack.pop())

    return binstrng

print  divide(25,2)