Loop and validation in number guessing game

Question

I have previously studied Visual Basic for Applications and am slowly getting up to speed with python this week. As I am a new programmer, please bear with me. I understand most of the concepts so far that I've encountered but currently am at a brick wall.

I've written a few functions to help me code a number guessing game. The user enters a 4 digit number. If it matches the programs generated one (I've coded this already) a Y is appended to the output list. If not, an N.

EG. I enter 4567, number is 4568. Output printed from the list is YYYN.

import random 

def A(): 
    digit = random.randint(0, 9)
    return digit 

def B(): 
    numList = list() 
    for counter in range(0,4):
        numList.append(A()) 
    return numList 


def X():
    output = []

    number = input("Please enter the first 4 digit number: ")

    number2= B()



for i in range(0, len(number)):
    if number[i] == number2[i]:
        results.append("Y")
    else:
        results.append("N") 

print(output)

X()

I've coded all this however theres a few things it lacks:

1. A loop. I don't know how I can loop it so I can get it to ask again. I only want the person to be able to guess 5 times. I'm imagining some sort of for loop with a counter like "From counter 1-5, when I reach 5 I end" but uncertain how to program this.

2. I've coded a standalone validation code snippet but don't know how I could integrate this in the loop, so for instance if someone entered 444a it should say that this is not a valid entry and let them try again. I made an attempt at this below.

   while myNumber.isnumeric() == True and len(myNumber) == 4:
       for i in range(0, 4)):  
           if myNumber[i] == progsNumber[i]:
               outputList.append("Y")
           else:
               outputList.append("N")
   

Made some good attempts at trying to work this out but struggling to patch it all together. Is anyone able to show me some direction into getting this all together to form a working program? I hope these core elements that I've coded might help you help me!

Answer 1

To answer both your questions:

1. Loops, luckily, are easy. To loop over some code five times you can set tries = 5, then do while tries > 0: and somewhere inside the loop do a tries -= 1.

   If you want to get out of the loop ahead of time (when the user answered correctly), you can simply use the break keyword to "break" out of the loop. You could also, if you'd prefer, set tries = 0 so loop doesn't continue iterating.

2. You'd probably want to put your validation inside the loop in an if (with the same statements as the while loop you tried). Only check if the input is valid and otherwise continue to stop with the current iteration of your loop and continue on to the next one (restart the while).

So in code:

answer = [random.randint(0, 9) for i in range(4)]

tries = 5
while tries > 0:
    number = input("Please enter the first 4 digit number: ")

    if not number.isnumeric() or not len(number) == len(answer):
        print('Invalid input!')
        continue

    out = ''
    for i in range(len(answer)):
        out += 'Y' if int(number[i]) == answer[i] else 'N'

    if out == 'Y' * len(answer):
        print('Good job!')
        break

    tries -= 1
    print(out)
else:
    print('Aww, you failed')

I also added an else after the while for when tries reaches zero to catch a failure (see the Python docs or maybe this SO answer)