'''

Created on Jun 4, 2018

@author: nishant.sethi

'''

class Stack:

def __init__(self):

self.stack = []

def add(self, dataval):

# Use list append method to add element

if dataval not in self.stack:

self.stack.append(dataval)

return True

else:

return False

# Use peek to look at the top of the stack

def peek(self):

return self.stack[0]

# Use list pop method to remove element

def remove(self):

if len(self.stack) <= 0:

return ("No element in the Stack")

else:

return self.stack.pop()