Short code with loop, function and list isn't working.Much appreciated if you help. (New at Python)

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Just started learning python, so I’m very thankful for anyone who can help.

Anyways the task is to define a function that takes a list of numbers and returns 3 values – how many positive numbers, negative numbers and zeroes there are in the list.

The main program I need to use a loop that gets the user to input however many numbers he wants (must be between 3 and 6, and this has to be checked). these numbers that the user inputs are to be added to a list. Then I have to call a function that uses the list as the argument and then print the results that the function returns.

using a loop is obligatory.

def three(z):
    np = 0
    nn = 0
    zeroes = 0
    
    for y in z:
        if x<0:
            nn+=1
        if x>0:
            np+=1
        if x==0:
            zeroes+=1
    
    print('there are ', np, ' positive numbers\nthere are ', nn, ' negative numbers\nthere are ', zeroes, ' zeros')
    
    return (np, nn, zeroes)

num_list = []

a = 0
n = eval(input('input a number (bigger than 3, smaller than 6): '))

while n>3 and n<6:
    if a < n:
        x = eval(input('input a number: '))
        num_list.append(x)
        a+= 1
    else:
        break
        
three(num_list)

I made a loop and a function, but I’m pretty sure I messed up at the loop or somewhere else because it looks like I’m using a lot of variables and it looks more complicated then it should probably be.

>Solution :

First, you should avoid using eval to get the numerical value of the user input. Ignatius Reilly left a good link to explain why in a comment. Instead, just cast the string input to int using int(input(...)) instead.

Second, the issue is that you are comparing x to zero. x is not defined in your function, so it looks outside the function scope and then pulls what you defined as x there, which is the last user input from x = eval(input(...)). So a user that inputs -1, 2, 0, 4 will return (4, 0, 0) because it just compares 4 to 0 four times rather than each individual input. You made a simple mistake here and should’ve used y in your if statements.

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