# Once fibonacci(n) is computed, table[n] will contain its value.

table = [] #Initially, we haven't computed any values.

def fibonacci(n):
    # Make sure the table is big enough.
    while len(table) <= n:
        table.append(None)
    # Now we can put the value into the table if it isn't already there.
    if table[n]==None:
        if n==0:
            table[n] = 0
        elif n==1:
            table[n] = 1
        else:
            table[n] = fibonacci(n-1) + fibonacci(n-2)
    # Now the value is in the table, so we can return it.
    return table[n]