45 lines
1.1 KiB
Text
45 lines
1.1 KiB
Text
|
\( Two arrays, iterative, not in lexical order.
|
||
|
|
Input row (a) provides for each element where it was inserted last.
|
||
|
|
\)
|
||
|
|
\C Publication syntax
|
||
|
|
permute iterative (n):
|
||
|
|
a = new row size n \ state of last number
|
||
|
|
r = new row size n \ output row
|
||
|
|
l = 1
|
||
|
|
while l > 0 \ need to start over
|
||
|
|
\ find the key of a void element
|
||
|
|
k = 0 \ if not found
|
||
|
|
for j = from a[l] + 1 upto n
|
||
|
|
if r[j] == () \ void in result
|
||
|
|
k = j \ use it
|
||
|
|
continue
|
||
|
|
\ evaluate
|
||
|
|
if k != 0
|
||
|
|
\ key for void cell to be set
|
||
|
|
r[k] = l
|
||
|
|
a[l] = k
|
||
|
|
if l == n
|
||
|
|
\ permuation complete
|
||
|
|
print join r
|
||
|
|
\ backup
|
||
|
|
k = a[l]
|
||
|
|
r[k] = ()
|
||
|
|
continue
|
||
|
|
l += 1
|
||
|
|
continue \ next level
|
||
|
|
\ no void cell found
|
||
|
|
if l == 1
|
||
|
|
break \ done, no more permutations
|
||
|
|
\ backup
|
||
|
|
a[l] = 0
|
||
|
|
l -= 1
|
||
|
|
k = a[l]
|
||
|
|
r[k] = ()
|
||
|
|
continue
|
||
|
|
|
||
|
|
\( command line parameter: number of elements
|
||
|
|
\)
|
||
|
|
main (parms):+
|
||
|
|
n =: string parms[1] as integer else 3
|
||
|
|
p =: permute iterative n
|