blob: 80a3a74d5953e88dc272314cd5ba395e35ba1eca (
plain)
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
|
// Ackermann function
`export ack : Fn[m; n] $ (
? !=(`type m; `type n) {
`exit "m and n must be the same type and above zero"
}
? {
m = 0 { n + 1 }
&(m > 0; n = 0) { ack `call_sync (m - 1; 1) }
&(m > 0; n > 0) { ack `call_sync (m - 1; ack `call_sync (m; n - 1)) }
{ 0 }
}
)
`export ack_string : Fn[m; n] $ (
String $ ("ack("; m; " "; n; ") = "; ack `call_sync (m; n); "\n")
)
`is_main Fn $ (
( args ) : `use "sys"
? 4 != `length args {
`return `error String $ (
"Got: "; " " `join args; "\n"
"Usage: "; args `get 0; " "; args `get 1; " <m> <n>\n"
)
}
`print ack_string `call_sync (I64 $ args `get -2; I64 $ args `get -1)
)
|
