How stack works and logic
If we imagine a stack horizontally then...
Element in stack is inserted in the same way we append an element to an array. So this logic could be used for the push function of our stack.
Element is popped from the end of the stack so we have a direct pop() function which can be implemented in the pop function for this. pop() removes the first element from a list so we use pop(-1) to remove the last element.
This was a question from GeeksForGeeks Practice
Ex: push(1), push(2), push(3), pop()
[1] [1,2] [1,2,3] [1,2]
Code
`class MyStack:
def __init__(self):
self.arr=[]
#Function to push an integer into the stack.
def push(self,data):
#add code here
self.arr.append(data)
#Function to remove an item from top of the stack.
def pop(self):
#add code here
if len(self.arr) > 0:
popped = self.arr.pop(-1)
return popped
else:
return -1`
Thank You. Hope you liked this solution. If there are better solutions or you have your own different solution then comment it below👍
Top comments (0)