Powershell, 147 byte (versione CodeGolf)
param($n)filter d{-join($(for($i=2;$_-ge$i*$i){if($_%$i){$i++}else{"$i"
$_/=$i}}if($_-1){"$_"})|% t*y|sort -d)}2..($s=$n|d)|?{$_-$n-and$s-eq($_|d)}
Nota: lo script risolve gli ultimi casi di test in meno di 3 minuti sul mio taccuino locale. Vedere la soluzione "prestazioni" di seguito.
Script di test meno golfato:
$g = {
param($n)
filter d{ # in the filter, Powershell automatically declares the parameter as $_
-join($( # this function returns a string with all digits of all prime divisors in descending order
for($i=2;$_-ge$i*$i){ # find all prime divisors
if($_%$i){
$i++
}else{
"$i" # push a divisor to a pipe as a string
$_/=$i
}
}
if($_-1){
"$_" # push a last divisor to pipe if it is not 1
}
)|% t*y|sort -d) # t*y is a shortcut to toCharArray method. It's very slow.
}
2..($s=$n|d)|?{ # for each number from 2 to number with all digits of all prime divisors in descending order
$_-$n-and$s-eq($_|d) # leave only those who have the 'all digits of all prime divisors in descending order' are the same
}
}
@(
,(2 ,'')
,(4 ,'')
,(6 ,23)
,(8 ,'')
,(15 ,53)
,(16 ,'')
,(23 ,6)
,(42 ,74, 146, 161)
,(107 ,701)
,(117 ,279, 939, 993, 3313, 3331)
,(126 ,222, 438, 483, 674, 746, 851, 1466, 1631, 1679)
,(204 ,364,548,692,762,782,852,868,1268,1626,2474,2654,2921,2951,3266,3446,3791,4274,4742,5426,5462,6233,6434,6542,7037,8561,14426,14642,15491,15833,22547)
) | % {
$n,$expected = $_
$sw = Measure-Command {
$result = &$g $n
}
$equals=$false-notin(($result|%{$_-in$expected})+($expected|?{$_-is[int]}|%{$_-in$result}))
"$sw : $equals : $n ---> $result"
}
Produzione:
00:00:00.0346911 : True : 2 --->
00:00:00.0662627 : True : 4 --->
00:00:00.1164648 : True : 6 ---> 23
00:00:00.6376735 : True : 8 --->
00:00:00.1591527 : True : 15 ---> 53
00:00:03.8886378 : True : 16 --->
00:00:00.0441986 : True : 23 ---> 6
00:00:01.1316642 : True : 42 ---> 74 146 161
00:00:01.0393848 : True : 107 ---> 701
00:00:05.2977238 : True : 117 ---> 279 939 993 3313 3331
00:00:12.1244363 : True : 126 ---> 222 438 483 674 746 851 1466 1631 1679
00:02:50.1292786 : True : 204 ---> 364 548 692 762 782 852 868 1268 1626 2474 2654 2921 2951 3266 3446 3791 4274 4742 5426 5462 6233 6434 6542 7037 8561 14426 14642 15491 15833 22547
Powershell, 215 byte (versione "Performance")
param($n)$p=@{}
filter d{$k=$_*($_-le3e3)
($p.$k=-join($(for($i=2;!$p.$_-and$_-ge$i*$i){if($_%$i){$i++}else{"$i"
$_/=$i}}if($_-1){($p.$_,"$_")[!$p.$_]})-split'(.)'-ne''|sort -d))}2..($s=$n|d)|?{$_-$n-and$s-eq($_|d)}
Nota: credo che i requisiti di prestazione siano in conflitto con il principio GodeGolf. Ma poiché c'era una regola Your program should solve any of the test cases below in less than a minute, ho fatto due modifiche per soddisfare la regola:
-split'(.)'-ne''invece il codice funzione |% t*y;- una hashtable per incassare le stringhe.
Ogni modifica riduce della metà il tempo di valutazione. Per favore, non pensare di aver usato tutte le funzionalità per migliorare le prestazioni. Erano sufficienti quelli per soddisfare la regola.
Script di test meno golfato:
$g = {
param($n)
$p=@{} # hashtable for 'all digits of all prime divisors in descending order'
filter d{ # this function returns a string with all digits of all prime divisors in descending order
$k=$_*($_-le3e3) # hashtable key: a large hashtable is not effective, therefore a key for numbers great then 3000 is 0
# and string '-le3e3' funny
($p.$k=-join($( # store the value to hashtable
for($i=2;!$p.$_-and$_-ge$i*$i){
if($_%$i){$i++}else{"$i";$_/=$i}
}
if($_-1){
($p.$_,"$_")[!$p.$_] # get a string with 'all digits of all prime divisors in descending order' from hashtable if it found
}
)-split'(.)'-ne''|sort -d)) # split each digit. The "-split'(.)-ne''" code is faster then '|% t*y' but longer.
}
2..($s=$n|d)|?{ # for each number from 2 to number with all digits of all prime divisors in descending order
$_-$n-and$s-eq($_|d) # leave only those who have the 'all digits of all prime divisors in descending order' are the same
}
}
@(
,(2 ,'')
,(4 ,'')
,(6 ,23)
,(8 ,'')
,(15 ,53)
,(16 ,'')
,(23 ,6)
,(42 ,74, 146, 161)
,(107 ,701)
,(117 ,279, 939, 993, 3313, 3331)
,(126 ,222, 438, 483, 674, 746, 851, 1466, 1631, 1679)
,(204 ,364,548,692,762,782,852,868,1268,1626,2474,2654,2921,2951,3266,3446,3791,4274,4742,5426,5462,6233,6434,6542,7037,8561,14426,14642,15491,15833,22547)
) | % {
$n,$expected = $_
$sw = Measure-Command {
$result = &$g $n
}
$equals=$false-notin(($result|%{$_-in$expected})+($expected|?{$_-is[int]}|%{$_-in$result}))
"$sw : $equals : $n ---> $result"
}
Produzione:
00:00:00.0183237 : True : 2 --->
00:00:00.0058198 : True : 4 --->
00:00:00.0181185 : True : 6 ---> 23
00:00:00.4389282 : True : 8 --->
00:00:00.0132624 : True : 15 ---> 53
00:00:04.4952714 : True : 16 --->
00:00:00.0128230 : True : 23 ---> 6
00:00:01.4112716 : True : 42 ---> 74 146 161
00:00:01.3676701 : True : 107 ---> 701
00:00:07.1192912 : True : 117 ---> 279 939 993 3313 3331
00:00:07.6578543 : True : 126 ---> 222 438 483 674 746 851 1466 1631 1679
00:00:50.5501853 : True : 204 ---> 364 548 692 762 782 852 868 1268 1626 2474 2654 2921 2951 3266 3446 3791 4274 4742 5426 5462 6233 6434 6542 7037 8561 14426 14642 15491 15833 22547
Ç€=$sarebbe un po 'più veloce diÇ€=Ç, dato il tempo limitato.