// fib memoised 2 Aug 2005

F = array 1000
count = 0

to fib n =
  if n < 2 
    F[n] = 1
    1 break
  if F[n] != 0
    F[n] break
  else
    count = count + 1
    F[n] = (fib n - 1) + (fib n - 2)
    F[n]

// recursive version
to fib2 n = 
  count = count + 1
  if n < 2 1
  else (fib2 n - 1) + (fib2 n - 2)

print fib 6 nl
print count nl
count = 0
print fib2 6 nl
print count nl