Will this variable script work?

Here is a script using variable with a loop

a = 2

b = 9

c = a+b

while true do
print(c)
wait(2)
print(b)
wait(2)
print(a)
wait(2)
end

The script is suppose to Print c (printing a+b which is 11) Then print b (which is 9) Then a (which is 2)

Help?

It works as intended for me. What's the problem?