stack in gfg code example
Example: stack in gfg
class StackNode:
def __init__(self, data):
self.data = data
self.next = None
class Stack:
def __init__(self):
self.root = None
def isEmpty(self):
return True if self.root is None else False
def push(self, data):
newNode = StackNode(data)
newNode.next = self.root
self.root = newNode
print "% d pushed to stack" % (data)
def pop(self):
if (self.isEmpty()):
return float("-inf")
temp = self.root
self.root = self.root.next
popped = temp.data
return popped
def peek(self):
if self.isEmpty():
return float("-inf")
return self.root.data
stack = Stack()
stack.push(10)
stack.push(20)
stack.push(30)
print "% d popped from stack" % (stack.pop())
print "Top element is % d " % (stack.peek())