extern printint(x: Integer)

fast_fibonacci(i: Integer): Integer do
    a: Integer
    b: Integer
    temp: Integer
    count: Integer
    count := i 
    a := 0
    b := 1
    while count != 0 do
        temp := a
        a := a + b
        b := temp
        count := count - 1
    end
    return a
end