def build_fib_iterative(n):
    """
    n: number of elements in the sequence
    Returns a Fibonacci sequence of n elements by iterative method
    """
    if n == 1:
        return [0]
    elif n == 2:
        return [0, 1]
    else:
        fib = [0, 1]
        count = 2

        while count < n:
            last_elem = fib[-1] + fib[-2]
            fib.append(last_elem)
            count += 1
            
        return fib