Question

A list, NList contains following record as list elements:

[City, Country, distance from Delhi] 

Each of these records are nested together to form a nested list. Write the following user defined functions in Python to perform the specified operations on the stack named travel.

1. Push_element(NList): It takes the nested list as an argument and pushes a list object containing name of the city and country, which are not in India and distance is less than 3500 km from Delhi.
2. Pop_element(): It pops the objects from the stack and displays them. Also, the function should display “Stack Empty” when there are no elements in the stack.

For example: If the nested list contains the following data:

NList=[["New York", "U.S.A.", 11734],
["Naypyidaw", "Myanmar", 3219],
["Dubai", "UAE", 2194],
["London", "England", 6693],
["Gangtok", "India", 1580],
["Columbo", "Sri Lanka", 3405]]

The stack should contain:

['Naypyidaw', 'Myanmar'],
['Dubai', 'UAE'],
['Columbo', 'Sri Lanka']

The output should be:

['Columbo', 'Sri Lanka']
['Dubai', 'UAE']
['Naypyidaw', 'Myanmar']
Stack Empty

Answer 1

travel = [ ]
def Push_element (NList) :
       for L in NList:
             if L[1] != "India" and L[2]<3500:
                     travel.append([L[0],L[1]])

def Pop_element ():
   while len(travel):
      print (travel.pop())
   else:
      print ("Stack Empty")