0b55f123 |
1 | /* |
2 | The Sieve of Eratosthenes (c. 276-196 BC) |
3 | Prints all prime numbers up to MAX |
4 | */ |
5 | #define MAX 25 |
6 | |
7 | mtype = { number, eof }; |
8 | |
9 | chan root = [0] of { mtype, int }; |
10 | |
11 | proctype sieve(chan c; int prime) |
12 | { chan child = [0] of { mtype, int }; |
13 | bool haschild; |
14 | int n; |
15 | |
16 | printf("MSC: %d is prime\n", prime); |
17 | end: do |
18 | :: c?number(n) -> |
19 | if |
20 | :: (n%prime) == 0 -> |
21 | printf("MSC: %d = %d*%d\n", n, prime, n/prime) |
22 | :: else -> |
23 | if |
24 | :: !haschild -> /* new prime */ |
25 | haschild = true; |
26 | run sieve(child, n); |
27 | :: else -> |
28 | child!number(n) |
29 | fi; |
30 | fi |
31 | :: c?eof(0) -> |
32 | break |
33 | od; |
34 | if |
35 | :: haschild -> |
36 | child!eof(0) |
37 | :: else |
38 | fi |
39 | } |
40 | |
41 | init |
42 | { int n = 2; |
43 | |
44 | run sieve(root, n); |
45 | do |
46 | :: (n < MAX) -> n++; root!number(n) |
47 | :: (n >= MAX) -> root!eof(0); break |
48 | od |
49 | } |