Complete the function that takes a non-negative integer n
as input, and returns a list of all the powers of
2
with the exponent ranging from 0
to n
(inclusive).
n = 0 ==> [1] # [2^0]
n = 1 ==> [1, 2] # [2^0, 2^1]
n = 2 ==> [1, 2, 4] # [2^0, 2^1, 2^2]
def powers_of_two(n)
(0..n).map { |n| 2**n }
end