Question

Please write the code in Python.

Write a program/function in any Object-Oriented programming language that will implement Queue Abstract Data Type with the following functions/methods.  Any build-in/pre-defined Queue function/library (e.g., java.util.Queue in Java) is NOT allowed to use in your code.

• push(Element):  insert the input Element (e.g., String or Integer in Java) to the end of the queue.
• pop(): remove the head element of the queue and print the head element on screen.
• count():  return the total number of elements in the queue

Your program/function will do the following steps:

1. take 1 input parameter, (e.g., String or Integer, in Java) to initialize your object type in the queue
2. after step #1, your program should display the following options (i.e., main screen) for grader to select any one of them to test out your program.
   1. push
   2. pop
   3. count
   4. end

When option (a) is selected, your program should enable grader to enter an element (e.g., TEST1) that will be inserted into the queue, and prompt the main screen to let grader to continue to select any one of options.

When option (b) is selected, your program should remove the element from the queue, and print out the head element (e.g., TEST1) on screen, and prompt the main screen to let grader to continue to select any one of options.  If the queue is empty when option (b) is selected, your program should display “There is no element in the queue” on screen and prompt the main screen to let grader to continue to select any one of options.

When option (c) is selected, your program should display the total number of elements in the queue and prompt the main screen to let grader to continue to select any one of options.

When option (d) is selected, your program will be terminated.

Please DO NOT hard-coded any input values, output values in your code.

Answer 1

queue = [] 
def push():
     element=input("Enter value : ")
     queue.append(element)

def Pop():
    if(len(queue)<=0):
        return "There is no element in the queue"
    else:
        return queue.pop(0)
    
def count():
    return len(queue)

if __name__ == "__main__":
    print("1.Push\n2.Pop\n3.Count\n4.Quit")
    while(True):
        ch=input("Enter choice : ")
        if(ch=="push"):
            push()
        if(ch=="pop"):
            print(Pop())
        if(ch=="count"):
            print(count())
        if(ch=="quit"):
            break