100 Doors Problem

100Doors.py

'''
100 Doors Problem:
There are 100 doors in a row that are all initially closed.
You make 100 passes by the doors.
The first time through, visit every door and  toggle  the door  (if the door is closed,  open it;   if it is open,  close it).
The second time, only visit every 2nd door   (door #2, #4, #6, ...),   and toggle it.
The third time, visit every 3rd door   (door #3, #6, #9, ...), etc,   until you only visit the 100th door.
Task:
Answer the question:   what state are the doors in after the last pass?   Which are open, which are closed?

Note: Edited to take input from user for number of doors.
'''

# Gets number of doors from user
def get_val():
    num_doors = input('Enter an integer greater than 0: ')
    try:
        if int(num_doors) > 0:
            return int(num_doors)
        else:
            print('I said greater than zero.')
            return get_val()
    except:
        print(num_doors + " is not an integer. Do it right.")
        return get_val()

# Creates doors in closed state using number entered by user
def create_doors(num_doors):
    doors = [False] * num_doors
    return doors

# Uses pass number to flip state of appropriate doors
# enumerate starting at 1 because the only time the first door should be flipped is on pass 1, 
# and 0%X=0.
def flip(doors,iter):
    for i, elem in enumerate(doors,1):
        if i%iter == 0:
            if doors[i-1] == True:
                doors[i-1] = False
            elif doors[i-1] == False:
                doors[i-1] = True
            print(i, elem)
    return doors

# Creates list of open doors and list of closed doors, displays results
def door_lists(doors):
    opened = []
    closed = []
    for i, elem in enumerate(doors):
        if elem == True:
            opened.append(i + 1)
        elif elem == False:
            closed.append(i + 1)
    print('Open Doors:')
    print(opened)
    print('Closed Doors:')
    print(closed)

# Calls functions to get values from user and create doors. Creates iterator, a list of pass numbers
num_doors = get_val()
doors = create_doors(num_doors)
iterator = list(range(1, num_doors + 1))

#For each pass (iterator value) call flip func to flip appropriate doors
for i in iterator:
    doors = flip(doors,i)

#display final results
door_lists(doors)