1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
|
# 10jul11abu
# (c) Software Lab. Alexander Burger
# Standard version
(de fibo (N)
(if (> 2 N)
1
(+ (fibo (dec N)) (fibo (- N 2))) ) )
# Parallelized version
(de fibo+ (D N) # Uses 2**D processes
(cond
((> 1 (dec 'N)) 1)
((ge0 (dec 'D))
(let (A NIL B NIL)
(later 'A (fibo+ D N))
(later 'B (fibo+ D (dec N)))
(wait NIL (and A B))
(+ A B) ) )
(T
(+
(fibo+ D N)
(fibo+ D (dec N)) ) ) ) )
# Using a cache (fastest)
(de cachedFibo (N)
(cache '(NIL) (pack (char (hash N)) N)
(if (> 2 N)
1
(+ (cachedFibo (dec N)) (cachedFibo (- N 2))) ) ) )
# Coded in 'C'
`(== 64 64) # Only in the 64-bit version
(load "@lib/native.l")
(gcc "fibo" NIL
(cFibo (N) "Fibo" 'I N) )
int Fibo(int n) {
if (n < 2)
return 1;
return Fibo(n-1) + Fibo(n-2);
}
/**/
# vi:et:ts=3:sw=3
|
