Q:

Countdown to zero instead of 1?

a = int(input("Enter a numeber: "))

for i in range(a):
    x = a - i
    print(x)

How can I make this count down to zero instead of 1?

A:

You could use the three-argument form of range:
for i in range(a, -1, -1):
     print(i)

It will start with a and then (because the step [third argument] is -1) count down to 0 because the stop value (-1 [second argument]) is excluded.

