Fibonacci sequence in Ruby (recursion)

Question

I\'m trying to implement the following function, but it keeps giving me the stack level too deep (SystemStackError) error.

Any ideas what the problem mi

Answer 1

a = [1, 1]
while(a.length < max) do a << a.last(2).inject(:+) end

This will populate a with the series. (You will have to consider the case when max < 2)

If only the nth element is required, You could use Hash.new

fib = Hash.new {|hsh, i| hsh[i] = fib[i-2] + fib[i-1]}.update(0 => 0, 1 => 1)

fib[10]
# => 55