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Joseph Carrillo
1,831 PointsHow to decrement using a for or while loop?
Hi Everyone,
I am new to Python programming. The code below works just fine but I want to decrement the initialized amount of tickets which is 100 until it hit zero tickets. For instance, below if you run my code, I enter the input of three; it outputs the difference of the initialized value of 100 and the result is 97 tickets. I want to loop so whenever the code runs it decrements until there are no more tickets.
Please see code below and your contributions or feedback is much appreciated.
#total tickets available
tickets_remaining = 100
#input from user
num_tickets = input("Hi customer! There are {} number of tickets left. How many tickets would you like to purchase? ".format(tickets_remaining))
#makes the input an integer
num_tickets = int(num_tickets)
#outputs the number of tickets they entered
print("You selected {} tickets you want to purchase.".format(num_tickets))
#prompts the user if this is the correct value that they entered
verify = input("Is this correct? Y/N? ")
#if the value is "Y" for yes then you take the initialized value minus the value the user inputs and output the remaining, else outputs another string.
if verify == "Y":
tickets_left = tickets_remaining - num_tickets
print("There are {} remaining tickets left. Thank you for your purchase.".format(tickets_left))
else :
print("Thank you for your inquiry. Have a great day!")
7 Answers
Christian Nogueras
298 PointsHmmm I don’t quite understand your question. You can create an while loop for example
while ticket_left > 0:
# Keep asking if they want to purchase more tickets
num_tickets = int(input("How many more ticket you want to purchase ? ")
ticket_left = ticket_left - num_tickets
exit_while_loop = str(input(“ Do you want to exist?. Enter ‘Y’ for yes and ‘N’ for no ”)
if exit_while_loop == Y:
break
Joseph Carrillo
1,831 PointsChristian Nogueras Thank you for your contributions and suggestions :)
Joseph Carrillo
1,831 PointsThank you in advance
Joseph Carrillo
1,831 PointsUpdate:
tickets_remaining = 100
num_tickets = input("Hi customer! There are {} number of tickets left. How many tickets would you like to purchase? ".format(tickets_remaining))
num_tickets = int(num_tickets)
print("You selected {} tickets you want to purchase.".format(num_tickets))
verify = input("Is this correct? Y/N? ")
while verify == "Y":
if tickets_remaining >= 0:
tickets_left = tickets_remaining - num_tickets
print("There are {} remaining tickets left. Thank you for your purchase.".format(tickets_left))
break
else :
print("Thank you for your inquiry. Have a great day!")
Joseph Carrillo
1,831 Pointstickets_remaining = 100
num_tickets = int(input("Hi customer! There are {} number of tickets left. How many tickets would you like to purchase? ".format(tickets_remaining)))
print("You selected {} tickets you want to purchase.".format(num_tickets))
if num_tickets == 0:
exit
else:
verify = input("Is this correct? Y/N? ")
if verify == "Y":
while (tickets_remaining >= num_tickets):
tickets_remaining = tickets_remaining - num_tickets
print("There are {} remaining tickets left. Thank you for your purchase.".format(tickets_remaining))
more_tickets = input("Would you like to purchase anymore tickets? Y/N? ")
if more_tickets == "Y":
num_tickets = num_tickets = int(input("How many more tickets would you like to purchase? ".format(tickets_remaining)))
else:
break
Joseph Carrillo
1,831 PointsSeems like I can achieve through repetitious if/else and nested if statements but that would clutter my code and require a lot of maintenance.
Joseph Carrillo
1,831 PointsChristian Nogueras does the code in my last post look correct?
Christian Nogueras
298 PointsI think that it would work for your purpose :)
Joseph Carrillo
1,831 PointsJoseph Carrillo
1,831 PointsThank you Christian. I wanted to make my code a slight different because I did not want to copy yours and find the root cause why code was executing the way I wanted it to. Last night, I was able to loop successfully but I could not get it to decrement correctly. I appreciate your efforts. I do want to try to accomplish using the for loop to use another method. I plan to use a function as well to condense my code but call on that function.