String Conversion Error "String index out of range" in python - python

Hello I'm asking about the conversion issue with strings and integers.
I have a piece code that requires the conversion between strings and integers but I just can't get it to work, I wonder if anyone could help me. I receive String index out of range error.
Here is the code
def ISBN(bc):
total = 0
up = 0
down = 11
for x in range(10):
sbc = str(bc)
ibc = int(sbc[up])
total += (ibc * down)
#total += (int(sbc[up])*down)
up += 1
down -+ 1
mod = (total % 12)
if mod == 10:
total = "x"
print ("The ISBN book code is: " + bc + total)
w = 0
while w == 0:
a = int(input("Please input the 10 digit book number:\n"))
b = str(a)
if len(b) == 9:
ISBN(a)
else:
print ("Sorry book code not 10 digits long")
restart = input("Would you like to use the book code changer again?\n")
restart = restart.lower
if restart == "yes" or restart == "y":
print ("--------------------------------------------------\n")
elif restart == "no" or restart == "n":
print ("Thank you for using the ISBN book code changer\n")
w = 1

if len(b) == 9:
This should be 10.
mod = (total % 12)
This should be 11.

Related

How to solve Luhn algoritm

there is a lot of information about how to write Luhn algortim. I'm trying it too and I think that I'am very close to succes but I have some mistake in my code and dont know where. The test card is VALID card but my algorithm says otherwise. Don't you know why? Thx for help
test = "5573497266530355"
kazde_druhe = []
ostatni = []
for i in test:
if int(i) % 2 == 0:
double_digit = int(i) * 2
if double_digit > 9:
p = double_digit - 9
kazde_druhe.append(p)
else:
kazde_druhe.append(double_digit)
else:
ostatni.append(int(i))
o = sum(ostatni)
k = sum(kazde_druhe)
total = o+k
if total % 10 == 0:
print(f"Your card is valid ")
else:
print(f"Your card is invalid ")
Finally! Thank you all for your help. Now it is working :-)
test = "5573497266530355" kazde_druhe = [] ostatni = []
for index, digit in enumerate(test):
if index % 2 == 0:
double_digit = int(digit) * 2
print(double_digit)
if double_digit > 9:
double_digit = double_digit - 9
kazde_druhe.append(double_digit)
else:
kazde_druhe.append(double_digit)
else:
ostatni.append(int(digit))
o = sum(ostatni)
k = sum(kazde_druhe)
total = o+k if total % 10 == 0:
print(f"Your card is valid ")
else:
print(f"Your card is invalid ")
From this description
2. With the payload, start from the rightmost digit. Moving left, double the value of every second digit (including the rightmost digit).
You have to check the digit position, not the number itself.
Change to this:
for i in range(len(test)):
if i % 2 == 0:
This code works. :)
I fixed you code as much as i could.
test = "5573497266530355"
#test = "3379513561108795"
nums = []
for i in range(len(test)):
if (i % 2) == 0:
num = int(test[i]) * 2
if num > 9:
num -= 9
nums.append(num)
else:
nums.append(int(test[i]))
print(nums)
print((sum(nums) % 10) == 0)
I found where your code went wrong.
On the line:
for i in test:
if int(i) % 2 == 0:
It should be:
for i in range(len(test)):
if i % 2 == 0:
You should not be using the element of the string you should be using the index of the element.

Luhn's algorithm works for all credit cards except for AMEX cards (Python3) (cs50/pset6/credit)

I'm trying to create a program that checks whether the credit card number the user inputed is either invalid, or from AMEX, MASTERCARD, or VISA. I'm using Luhn's formula. Here is a site that contains the explanation to the formula I'm using: https://www.geeksforgeeks.org/luhn-algorithm/
It works with all credit card numbers, except credit cards from AMEX. Could someone help me?
Here is my code:
number = input("Number: ")
valid = False
sumOfOdd = 0
sumOfEven = 0
def validation(credit_num):
global sumOfOdd
global sumOfEven
position = 0
for i in credit_num:
if position % 2 != 0:
sumOfOdd += int(i)
else:
product_greater = str(int(i) * 2)
if len(product_greater) > 1:
sumOfEven += (int(product_greater[0]) + int(product_greater[1]))
else:
sumOfEven += int(product_greater)
position += 1
def main():
if (sumOfOdd + sumOfEven) % 10 == 0:
if number[0] == "3":
print("AMEX")
elif number[0] == "5":
print("MASTERCARD")
else:
print("VISA")
else:
print("INVALID")
print(f"{sumOfOdd + sumOfEven}")
validation(number)
main()
Here are some credit card numbers:
VISA: 4111111111111111
MASTERCARD: 5555555555554444
AMEX: 371449635398431
I've found many different ways to calculate this formula, but I'm not sure if mine is correct.

Mastermind Python coding

Ok I have a feeling that this is a simple simple issue but I have been staring at this code for about 10 hours now.
The issue I am having is in mastermind is that once I get it to recognize that I have the correct colors in the right spot I can get it to display the right spots with X and the wrong spots with O. I need to be able to convert that so instead of X and O I need it to tell the user that he/she has 2 blacks and one white
For example: The secret code is RGYB The user enters RGOY so then Python relays "You have 2 blacks(The R and G spots) and one 1 White (The Y because it's the right color just in the wrong index) As of right now I got it to display X for the right color in the right spot and anything else it is an O
I will post what I have been working with now but today I am at my wit's end
https://pastebin.com/HKK0T7bQ
if correctColor != "XXXX":
for i in range(4):
if guess[i] == tempCode[i]:
correctColor += "X"
if guess[i] != tempCode[i] in tempCode:
correctColor += "O"
print (correctColor + "\n")
if correctColor == "XXXX":
if attempts == 1:
print ("You think you are sweet because you got it right on the first try? Play me again!")
else:
print ("Well done... You needed " + str(attempts) + " attempts to guess.")
game = False
A few comments
X and O
you use X and 0 to denote the success, it will be easier and faster to use a list or tuple or booleans for this, that way you can use sum() to count how many colors and locations were correct. Then whether you represent that with X and O or red and white pins is a matter for later
compartmentalization
Your game logic (guess input, input validation, do you want to continue, etc) is mixed with the comparison logic, so it would be best to separate the different functions of your program into different methods.
This is an fineexample to introduce object oriented programming, but is so simple it doesn't need OO, but it can help. What you need is a method which takes a series of colours and compares it to another series of colours
Standard library
Python has a very extended standard library, so a lot of stuff you want to do probably already exists
Correct colours
to count the number of letters which occur in 2 strings, you can use collections.Counter
guess = "RGOY "
solution = "RGYB"
a = collections.Counter(guess)
b = collections.Counter(solution)
a & b
Counter({'G': 1, 'R': 1, 'Y': 1})
correct_colours = sum((a & b).values())
3
So the user guessed 3 colours correctly
Correct locations
can be solved with an easy list comprehension
[g == s for g, s in zip(guess, solution)]
[True, True, False, False]
sum(g == s for g, s in zip(guess, solution))
2
so the used put 2 colours on the correct location
This is a MasterMind I made in Python. Hope you like it and it helped you! :)
import random
import time
from tkinter import *
def select_level():
global level
level = level_selector.get()
root.destroy()
root = Tk()
level_selector = Scale(root, from_=1, to=3, tickinterval=1)
level_selector.set(0)
level_selector.pack()
Button(root, text="Select a difficulty level", command=select_level).pack()
mainloop()
cpc_1_digit = 0
cpc_2_digit = 0
cpc_3_digit = 0
cpc_4_digit = 0
p_1_digit = 0
p_2_digit = 0
p_3_digit = 0
p_4_digit = 0
correct_correct = 0
correct_wrong = 0
chances = 0
if level == 1:
chances = 15
elif level == 2:
chances = 10
else:
chances = 7
cpc_1_digit = random.randint(0, 9)
while cpc_2_digit == cpc_1_digit or cpc_2_digit == cpc_3_digit or cpc_2_digit ==
cpc_4_digit:
cpc_2_digit = random.randint(0, 9)
while cpc_3_digit == cpc_1_digit or cpc_3_digit == cpc_2_digit or cpc_3_digit ==
cpc_4_digit:
cpc_3_digit = random.randint(0, 9)
while cpc_4_digit == cpc_1_digit or cpc_4_digit == cpc_2_digit or cpc_4_digit ==
cpc_3_digit:
cpc_4_digit = random.randint(0, 9)
while chances > 0:
correct_correct = 0
correct_wrong = 0
answer = input("Enter a four-digit number with different digits (e.g 1476): ")
p_1_digit = int(answer[0])
p_2_digit = int(answer[1])
p_3_digit = int(answer[2])
p_4_digit = int(answer[3])
if p_1_digit == cpc_1_digit:
correct_correct = int(correct_correct) + 1
elif p_1_digit == cpc_2_digit or p_1_digit == cpc_3_digit or p_1_digit ==
cpc_4_digit:
correct_wrong = int(correct_wrong) + 1
else:
pass
if p_2_digit == cpc_2_digit:
correct_correct = correct_correct + 1
elif p_2_digit == cpc_1_digit or p_2_digit == cpc_3_digit or p_2_digit ==
cpc_4_digit:
correct_wrong = int(correct_wrong) + 1
else:
pass
if p_3_digit == cpc_3_digit:
correct_correct = int(correct_correct) + 1
elif p_3_digit == cpc_1_digit or p_3_digit == cpc_2_digit or p_3_digit ==
cpc_4_digit:
correct_wrong = int(correct_wrong) + 1
else:
pass
if p_4_digit == cpc_4_digit:
correct_correct = int(correct_correct) + 1
elif p_4_digit == cpc_1_digit or p_4_digit == cpc_3_digit or p_4_digit ==
cpc_2_digit:
correct_wrong = int(correct_wrong) + 1
else:
pass
print("")
if int(correct_correct) == 4:
print("Congratsulations! You found the computer's number!")
break
elif int(correct_wrong) > 0 or int(correct_correct) >= 1 and int(correct_correct)
< 4:
print("You got " + str(correct_correct) + " correct digit(s) in the correct
place, and " + str(correct_wrong) + " correct digit(s) but in wrong place.")
elif int(correct_correct) == 0 and int(correct_wrong) == 0:
print("You didn't guess any number, try again!")
else:
raise Exception("CheckError: line 69, something went wrong with the
comparings.")
exit()
print("")
chances = chances - 1
if chances == 0:
print("You lost... The secret number was " + str(cpc_1_digit) + str(cpc_2_digit)
+ str(cpc_3_digit) + str(cpc_4_digit) + ". Try again by rerunning the program.")
time.sleep(4)

Trouble with Python Code. Objective is to code suffix during input

Objective: Write a function that takes an integer as its only parameter and returns the ordinal abbreviation for that integer as its only result. For example, if your function is passed the integer 1 then it should return the string "1st". If it is passed the integer 12 then it should return the string "12th". If it is passed 2003 then it should return the string "2003rd". Your function must not print anything on the screen.
def convert (n):
self.num = num
n = int(self.num)
if 4 <= n <= 20:
suffix = 'th'
elif n == 1 or (n % 10) == 1:
suffix = 'st'
elif n == 2 or (n % 10) == 2:
suffix = 'nd'
elif n == 3 or (n % 10) == 3:
suffix = 'rd'
elif n < 100:
suffix = 'th'
ord_num = str(n) + suffix
return ord_num
def main ():
day = int(input("Enter the day:"))
month = int(input("Enter the month:"))
year = int(input("Enter the year:"))
print("on the %n" %n, convert(day), "day of the %n" %month,
convert(month), "month of the %n" %year, convert(year),",
something amazing happened!")
main()
This is my code however it keeps saying I haven't defined n when I run it. But above I've already defined it so not sure what the problem is.
This is probably closer to what you want:
def convert(n):
n = int(n)
suffix = ''
if 4 <= n <= 20:
suffix = 'th'
elif n == 1 or (n % 10) == 1:
suffix = 'st'
elif n == 2 or (n % 10) == 2:
suffix = 'nd'
elif n == 3 or (n % 10) == 3:
suffix = 'rd'
elif n < 100:
suffix = 'th'
return str(n) + suffix
def main ():
day = int(input("Enter the day: "))
month = int(input("Enter the month: "))
year = int(input("Enter the year: "))
print("on the %s day of the %s month of the %s, something amazing happened!" %
(convert(day), convert(month), convert(year)))
main()
There are few issues. You cannot use n in main() when you define it in convert(). Also %n is not a valid format character. You need to define suffix = '' when also want run the year through the conversion function as the year can be larger than 100. Also, you probably copied the code from within a class definition. I removed the self.

python: program hanging! (print issue maybe?)

So, I'm quite nooby at python. I decided to make a program that makes prime numbers. I know there's probably a function built in that does this but I decided to do it myself.
number = 1
numlist = list()
for x in range (0, 1000):
numlist.append("")
print "Created list entry " + str(x)
while True:
number = number + 1
if number % 2 != 0:
numscrollerA = 1
numscrollerB = 1
while numscrollerA <= number:
if float(number) / float(numscrollerA) == float(int(number)):
numlist[numscrollerA] = "true"
if float(number) / float(numscrollerA) != float(int(number)):
numlist[numscrollerA] = "false"
numscrollerA = numscrollerA + 1
while numscrollerB <= number:
if numscrollerB != 1 and numscroller != number and numlist[numscrollerB] == "true":
primestatus = "false"
else:
primestatus = "true"
if primestatus == "true":
print number
I get "Created list entry x" 1000 times as I should. Then the program just hangs.
while numscrollerB <= number:
if numscrollerB != 1 and numscroller != number and numlist[numscrollerB] == "true":
primestatus = "false"
else:
primestatus = "true"
You don't increase numscrollerB in this loop, so it runs infinitedly. Anyway, You should rather use 'for loop':
for numscrollerB in range(1, number+1):
pass # do something
Your code is very unpythonic. Typical of a newcomer experienced in a different style of coding.
Your list is uneccessary.
In python you could create the list like this
def check_even(val):
#this contains your logic
return val % 2 == 0
evenslist = [check_even(i) for i in xrange(1, 1001)]
print numlist

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