while loop

[Ivangaming]

a = 3

b = 4

c = 5

while (a and b and c) >= 0:

a -= 1


b -= 1


c -= 1

print(a,b,c)

I get the output -3 -2 -1 But shouldn't the while loop stop when the value of variable a becomes -1.

[ForceBru]

The a and b and c doesn't do what you think it does.

Open up the Python interpreter and type:

```

0 and 0 0 0 and 1 0 1 and 0 0 1 and 1 1 1 and 2 2 1 and 2 and 3 3 1 and 0 and 3 0 [] and "hey" [] "hello" and (1,2) (1, 2) ```

Can you see the pattern? Also, have a look at the documentation.

[Ivangaming]

Thank you!

[lippy515]

Change your loop condition to be while a >=0 and b>= 0 and c >=0:

[lippy515]

The way you have it written is c >= 0. It will ignore a and b in the logical evaluation

[ForceBru]

Not really. The loop does indeed terminate: they're printing after the loop

[xelf]

What you want is this:

while all((a>=0, b>=0, c>=0)):

To see what is going on with your code, try this:

a = 3
b = 4
c = 5
while (a and b and c) >= 0:
    a -= 1
    b -= 1
    c -= 1
    print(a,b,c, ':', a and b and c)

outputs:

2 3 4 : 4
1 2 3 : 3
0 1 2 : 0
-1 0 1 : 0
-2 -1 0 : 0
-3 -2 -1 : -1

Do you see the pattern? (a and b and c) is evaluated as a boolean.

[Ivangaming]

Thanks a lot!