Lucky and even lucky numbers
You are encouraged to solve this task according to the task description, using any language you may know.
Note that in the following explanation list indices are assumed to start at one.
- Definition of lucky numbers
Lucky numbers are positive integers that are formed by:
- Form a list of all the positive odd integers > 0
- Return the first number from the list (which is 1).
- (Loop begins here)
- Note then return the second number from the list (which is 3).
- Discard every third, (as noted), number from the list to form the new list
- (Expanding the loop a few more times...)
- Note then return the third number from the list (which is 7).
- Discard every 7th, (as noted), number from the list to form the new list
- Note then return the 4th number from the list (which is 9).
- Discard every 9th, (as noted), number from the list to form the new list
- Take the 5th, i.e. 13. Remove every 13th.
- Take the 6th, i.e. 15. Remove every 15th.
- Take the 7th, i.e. 21. Remove every 21th.
- Take the 8th, i.e. 25. Remove every 25th.
- (Rule for the loop)
- Note the th, which is .
- Remove every th.
- Increment .
- Definition of even lucky numbers
This follows the same rules as the definition of lucky numbers above except for the very first step:
- Form a list of all the positive even integers > 0
- Return the first number from the list (which is 2).
- (Loop begins here)
- Note then return the second number from the list (which is 4).
- Discard every 4th, (as noted), number from the list to form the new list
- (Expanding the loop a few more times...)
- Note then return the third number from the list (which is 6).
- Discard every 6th, (as noted), number from the list to form the new list
- Take the 4th, i.e. 10. Remove every 10th.
- Take the 5th, i.e. 12. Remove every 12th.
- (Rule for the loop)
- Note the th, which is .
- Remove every th.
- Increment .
- Task requirements
- Write one or two subroutines (functions) to generate lucky numbers and even lucky numbers
- Write a command-line interface to allow selection of which kind of numbers and which number(s). Since input is from the command line, tests should be made for the common errors:
- missing arguments
- too many arguments
- number (or numbers) aren't legal
- misspelled argument (lucky or evenLucky)
- The command line handling should:
- support mixed case handling of the (non-numeric) arguments
- support printing a particular number
- support printing a range of numbers by their index
- support printing a range of numbers by their values
- The resulting list of numbers should be printed on a single line.
The program should support the arguments:
what is displayed (on a single line) argument(s) (optional verbiage is encouraged) ╔═══════════════════╦════════════════════════════════════════════════════╗ ║ j ║ Jth lucky number ║ ║ j , lucky ║ Jth lucky number ║ ║ j , evenLucky ║ Jth even lucky number ║ ║ ║ ║ ║ j k ║ Jth through Kth (inclusive) lucky numbers ║ ║ j k lucky ║ Jth through Kth (inclusive) lucky numbers ║ ║ j k evenLucky ║ Jth through Kth (inclusive) even lucky numbers ║ ║ ║ ║ ║ j -k ║ all lucky numbers in the range j ──► |k| ║ ║ j -k lucky ║ all lucky numbers in the range j ──► |k| ║ ║ j -k evenLucky ║ all even lucky numbers in the range j ──► |k| ║ ╚═══════════════════╩════════════════════════════════════════════════════╝ where |k| is the absolute value of k
Demonstrate the program by:
- showing the first twenty lucky numbers
- showing the first twenty even lucky numbers
- showing all lucky numbers between 6,000 and 6,100 (inclusive)
- showing all even lucky numbers in the same range as above
- showing the 10,000th lucky number (extra credit)
- showing the 10,000th even lucky number (extra credit)
- See also
- This task is related to the Sieve of Eratosthenes task.
- OEIS Wiki Lucky numbers.
- Sequence A000959 lucky numbers on The On-Line Encyclopedia of Integer Sequences.
- Sequence A045954 even lucky numbers or ELN on The On-Line Encyclopedia of Integer Sequences.
- Entry lucky numbers on The Eric Weisstein's World of Mathematics.
D
<lang D>import std.algorithm; import std.concurrency; import std.conv; import std.getopt; import std.range; import std.stdio;
auto lucky(bool even, int nmax=200_000) {
import std.container.array;
int start = even ? 2 : 1;
return new Generator!int({ auto ln = make!(Array!int)(iota(start,nmax,2));
// yield the first number yield(ln[0]);
int n=1; for(; n<ln.length/2+1; n++) { yield(ln[n]);
int step = ln[n]-1;
// remove the non-lucky numbers related to the current lucky number for (int i=step; i<ln.length; i+=step) { ln.linearRemove(ln[].drop(i).take(1)); } }
// yield all remaining values foreach(val; ln[n..$]) { yield(val); } });
}
void help(Option[] opt) {
defaultGetoptPrinter("./lucky j [k] [--lucky|--evenLucky]", opt);
writeln; writeln(" argument(s) | what is displayed"); writeln("=============================================="); writeln("-j=m | mth lucky number"); writeln("-j=m --lucky | mth lucky number"); writeln("-j=m --evenLucky | mth even lucky number"); writeln("-j=m -k=n | mth through nth (inclusive) lucky numbers"); writeln("-j=m -k=n --lucky | mth through nth (inclusive) lucky numbers"); writeln("-j=m -k=n --evenLucky | mth through nth (inclusive) even lucky numbers"); writeln("-j=m -k=-n | all lucky numbers in the range [m, n]"); writeln("-j=m -k=-n --lucky | all lucky numbers in the range [m, n]"); writeln("-j=m -k=-n --evenLucky | all even lucky numbers in the range [m, n]");
}
void main(string[] args) {
int j; int k; bool evenLucky = false;
void luckyOpt() { evenLucky = false; } auto helpInformation = getopt( args, std.getopt.config.passThrough, std.getopt.config.required, "j", "The starting point to generate lucky numbers", &j, "k", "The ending point for generating lucky numbers", &k, "lucky", "Specify to generate a list of lucky numbers", &luckyOpt, "evenLucky", "Specify to generate a list of even lucky numbers", &evenLucky );
if (helpInformation.helpWanted) { help(helpInformation.options); return; }
if (k>0) { lucky(evenLucky).drop(j-1).take(k-j+1).writeln; } else if (k<0) { auto f = (int a) => j<=a && a<=-k; lucky(evenLucky, -k).filter!f.writeln; } else { lucky(evenLucky).drop(j-1).take(1).writeln; }
}</lang>
- Output:
.\lucky_and_even_lucky_numbers.exe -j=1 -k=20 [1, 3, 7, 9, 13, 15, 21, 25, 31, 33, 37, 43, 49, 51, 63, 67, 69, 73, 75, 79] .\lucky_and_even_lucky_numbers.exe -j=1 -k=20 --evenLucky [2, 4, 6, 10, 12, 18, 20, 22, 26, 34, 36, 42, 44, 50, 52, 54, 58, 68, 70, 76] .\lucky_and_even_lucky_numbers.exe -j=6000 -k=-6100 [6009, 6019, 6031, 6049, 6055, 6061, 6079, 6093] .\lucky_and_even_lucky_numbers.exe -j=6000 -k=-6100 --evenLucky [6018, 6020, 6022, 6026, 6036, 6038, 6050, 6058, 6074, 6090, 6092] .\lucky_and_even_lucky_numbers.exe -j=10000 [115591] .\lucky_and_even_lucky_numbers.exe -j=10000 --evenLucky [111842]
Go
<lang go>package main
import (
"fmt" "log" "os" "strconv" "strings"
)
const luckySize = 60000
var luckyOdd = make([]int, luckySize) var luckyEven = make([]int, luckySize)
func init() {
for i := 0; i < luckySize; i++ { luckyOdd[i] = i*2 + 1 luckyEven[i] = i*2 + 2 }
}
func filterLuckyOdd() {
for n := 2; n < len(luckyOdd); n++ { m := luckyOdd[n-1] end := (len(luckyOdd)/m)*m - 1 for j := end; j >= m-1; j -= m { copy(luckyOdd[j:], luckyOdd[j+1:]) luckyOdd = luckyOdd[:len(luckyOdd)-1] } }
}
func filterLuckyEven() {
for n := 2; n < len(luckyEven); n++ { m := luckyEven[n-1] end := (len(luckyEven)/m)*m - 1 for j := end; j >= m-1; j -= m { copy(luckyEven[j:], luckyEven[j+1:]) luckyEven = luckyEven[:len(luckyEven)-1] } }
}
func printSingle(j int, odd bool) error {
if odd { if j >= len(luckyOdd) { return fmt.Errorf("the argument, %d, is too big", j) } fmt.Println("Lucky number", j, "=", luckyOdd[j-1]) } else { if j >= len(luckyEven) { return fmt.Errorf("the argument, %d, is too big", j) } fmt.Println("Lucky even number", j, "=", luckyEven[j-1]) } return nil
}
func printRange(j, k int, odd bool) error {
if odd { if k >= len(luckyOdd) { return fmt.Errorf("the argument, %d, is too big", k) } fmt.Println("Lucky numbers", j, "to", k, "are:") fmt.Println(luckyOdd[j-1 : k]) } else { if k >= len(luckyEven) { return fmt.Errorf("the argument, %d, is too big", k) } fmt.Println("Lucky even numbers", j, "to", k, "are:") fmt.Println(luckyEven[j-1 : k]) } return nil
}
func printBetween(j, k int, odd bool) error {
var r []int if odd { max := luckyOdd[len(luckyOdd)-1] if j > max || k > max { return fmt.Errorf("at least one argument, %d or %d, is too big", j, k) } for _, num := range luckyOdd { if num < j { continue } if num > k { break } r = append(r, num) } fmt.Println("Lucky numbers between", j, "and", k, "are:") fmt.Println(r) } else { max := luckyEven[len(luckyEven)-1] if j > max || k > max { return fmt.Errorf("at least one argument, %d or %d, is too big", j, k) } for _, num := range luckyEven { if num < j { continue } if num > k { break } r = append(r, num) } fmt.Println("Lucky even numbers between", j, "and", k, "are:") fmt.Println(r) } return nil
}
func main() {
nargs := len(os.Args) if nargs < 2 || nargs > 4 { log.Fatal("there must be between 1 and 3 command line arguments") } filterLuckyOdd() filterLuckyEven() j, err := strconv.Atoi(os.Args[1]) if err != nil || j < 1 { log.Fatalf("first argument, %s, must be a positive integer", os.Args[1]) } if nargs == 2 { if err := printSingle(j, true); err != nil { log.Fatal(err) } return }
if nargs == 3 { k, err := strconv.Atoi(os.Args[2]) if err != nil { log.Fatalf("second argument, %s, must be an integer", os.Args[2]) } if k >= 0 { if j > k { log.Fatalf("second argument, %d, can't be less than first, %d", k, j) } if err := printRange(j, k, true); err != nil { log.Fatal(err) } } else { l := -k if j > l { log.Fatalf("second argument, %d, can't be less in absolute value than first, %d", k, j) } if err := printBetween(j, l, true); err != nil { log.Fatal(err) } } return }
var odd bool switch lucky := strings.ToLower(os.Args[3]); lucky { case "lucky": odd = true case "evenlucky": odd = false default: log.Fatalf("third argument, %s, is invalid", os.Args[3]) } if os.Args[2] == "," { if err := printSingle(j, odd); err != nil { log.Fatal(err) } return }
k, err := strconv.Atoi(os.Args[2]) if err != nil { log.Fatal("second argument must be an integer or a comma") } if k >= 0 { if j > k { log.Fatalf("second argument, %d, can't be less than first, %d", k, j) } if err := printRange(j, k, odd); err != nil { log.Fatal(err) } } else { l := -k if j > l { log.Fatalf("second argument, %d, can't be less in absolute value than first, %d", k, j) } if err := printBetween(j, l, odd); err != nil { log.Fatal(err) } }
}</lang>
- Output:
$ ./lucky 1 20 Lucky numbers 1 to 20 are: [1 3 7 9 13 15 21 25 31 33 37 43 49 51 63 67 69 73 75 79] $ ./lucky 1 20 evenLucky Lucky even numbers 1 to 20 are: [2 4 6 10 12 18 20 22 26 34 36 42 44 50 52 54 58 68 70 76] $ ./lucky 6000 -6100 Lucky numbers between 6000 and 6100 are: [6009 6019 6031 6049 6055 6061 6079 6093] $ ./lucky 6000 -6100 evenLucky Lucky even numbers between 6000 and 6100 are: [6018 6020 6022 6026 6036 6038 6050 6058 6074 6090 6092] $ ./lucky 10000 , lucky Lucky number 10000 = 115591 $ ./lucky 10000 , evenLucky Lucky even number 10000 = 111842
Haskell
Haskell is a very nice language for this problem because it is a lazy language. Here regular expressions and data types are used. <lang Haskell> import System.Environment import Text.Regex.Posix
data Lucky = Lucky | EvenLucky
helpMessage :: IO () helpMessage = do
putStrLn " what is displayed (on a single line)" putStrLn " argument(s) (optional verbiage is encouraged)" putStrLn "======================|===================================================" putStrLn " j | Jth lucky number " putStrLn " j , lucky | Jth lucky number " putStrLn " j , evenLucky | Jth even lucky number " putStrLn " " putStrLn " j k | Jth through Kth (inclusive) lucky numbers " putStrLn " j k lucky | Jth through Kth (inclusive) lucky numbers " putStrLn " j k evenlucky | Jth through Kth (inclusive) even lucky numbers " putStrLn " " putStrLn " j -k | all lucky numbers in the range j -> |k| " putStrLn " j -k lucky | all lucky numbers in the range j -> |k| " putStrLn " j -k evenlucky | all even lucky numbers in the range j -> |k| " putStrLn "======================|==================================================="
oddNumbers :: [Int] oddNumbers = filter odd [1..]
evenNumbers :: [Int] evenNumbers = filter even [1..]
luckyNumbers :: [Int] -> [Int] luckyNumbers xs =
let i = 3 in sieve i xs where sieve i (ln:s:xs) = ln : sieve (i + 1) (s : [x | (n, x) <- zip [i..] xs, rem n s /= 0])
nth :: Int -> Lucky -> Int nth j Lucky = luckyNumbers oddNumbers !! (j-1) nth j EvenLucky = luckyNumbers evenNumbers !! (j-1)
range :: Int -> Int -> Lucky -> [Int] range x x2 Lucky = drop (x-1) (take x2 (luckyNumbers oddNumbers)) range x x2 EvenLucky = drop (x-1) (take x2 (luckyNumbers evenNumbers))
interval :: Int -> Int -> Lucky -> [Int] interval x x2 Lucky = dropWhile (<x) (takeWhile (<=x2) (luckyNumbers oddNumbers)) interval x x2 EvenLucky = dropWhile (<x) (takeWhile (<=x2) (luckyNumbers evenNumbers))
lucky :: [String] -> Lucky lucky xs =
if "evenLucky" `elem` xs then EvenLucky else Lucky
readn :: String -> Int readn s = read s :: Int
isInt :: String -> Bool isInt s = not (null (s =~ "-?[0-9]{0,10}" :: String))
main :: IO () main = do
args <- getArgs if head args == "--help" || null args then helpMessage else let l = lucky args in case map readn (filter isInt args) of [] -> do putStrLn "Invalid input, missing arguments" putStrLn "Type --help" [x] -> print (nth x l) [x, x2] -> if x2 > 0 then print (range x x2 l) else print (interval x (-x2) l) _ -> do putStrLn "Invalid input, wrong number of arguments" putStrLn "Type --help"</lang>
- Output:
$ luckyNumbers 1 20 [1,3,7,9,13,15,21,25,31,33,37,43,49,51,63,67,69,73,75,79] $ luckyNumbers 1 20 evenLucky [2,4,6,10,12,18,20,22,26,34,36,42,44,50,52,54,58,68,70,76] $ luckyNumbers 6000 -6100 lucky [6009,6019,6031,6049,6055,6061,6079,6093] $ luckyNumbers 6000 -6100 evenLucky [6018,6020,6022,6026,6036,6038,6050,6058,6074,6090,6092] $ luckyNumbers 10000 115591 $ luckyNumbers 10000 evenLucky 111842
J
Not going for extra credit because I want to encourage functional reactive "types" in J. (Note that FRP, along with an ML typed compiler, would probably remove the motivation for the while loop in this implementation.)
Implementation:
<lang J>luckySeq=:3 :0
1 luckySeq y
len=.0 nth=.0 seq=.x+2*i.4*y while. len~:#seq do. len=. #seq nth=. nth+1 seq=. nth exclude seq end.
)
exclude=: ] #~ 1 - #@] $ -@{ {. 1:
lucky=: evenLucky=:0 program=:3 :0
range=: |y-.0 seq=. (1+0 e.y) luckySeq >./range if. 0><./y do. (#~ e.&(thru/range)) seq else. (<:thru/range) { seq end.
)
thru=: <./ + i.@(+*)@-~</lang>
Task:
<lang J> program 1 20 1 3 7 9 13 15 21 25 31 33 37 43 49 51 63 67 69 73 75 79
program 1 20,evenLucky
2 4 6 10 12 18 20 22 26 34 36 42 44 50 52 54 58 68 70 76
program 6000,-6100
6009 6019 6031 6049 6055 6061 6079 6093
program 6000,-6100,evenLucky
6018 6020 6022 6026 6036 6038 6050 6058 6074 6090 6092</lang>
Note that I've used the J command line rather than a unix or windows command line. This is because J is portable to a wide variety of environments (including phones) and there's no reliably common command line that exists across all these environments. Therefore, J must provide its own, and J's command line requires some slight syntax changes from the suggestions implicit in this task.
Kotlin
<lang scala>// version 1.1.51
typealias IAE = IllegalArgumentException
val luckyOdd = MutableList(100000) { it * 2 + 1 } val luckyEven = MutableList(100000) { it * 2 + 2 }
fun filterLuckyOdd() {
var n = 2 while (n < luckyOdd.size) { val m = luckyOdd[n - 1] val end = (luckyOdd.size / m) * m - 1 for (j in end downTo m - 1 step m) luckyOdd.removeAt(j) n++ }
}
fun filterLuckyEven() {
var n = 2 while (n < luckyEven.size) { val m = luckyEven[n - 1] val end = (luckyEven.size / m) * m - 1 for (j in end downTo m - 1 step m) luckyEven.removeAt(j) n++ }
}
fun printSingle(j: Int, odd: Boolean) {
if (odd) { if (j >= luckyOdd.size) throw IAE("Argument is too big") println("Lucky number $j = ${luckyOdd[j - 1]}") } else { if (j >= luckyEven.size) throw IAE("Argument is too big") println("Lucky even number $j = ${luckyEven[j - 1]}") }
}
fun printRange(j: Int, k: Int, odd: Boolean) {
if (odd) { if (k >= luckyOdd.size) throw IAE("Argument is too big") println("Lucky numbers $j to $k are:\n${luckyOdd.drop(j - 1).take(k - j + 1)}") } else { if (k >= luckyEven.size) throw IAE("Argument is too big") println("Lucky even numbers $j to $k are:\n${luckyEven.drop(j - 1).take(k - j + 1)}") }
}
fun printBetween(j: Int, k: Int, odd: Boolean) {
val range = mutableListOf<Int>() if (odd) { val max = luckyOdd[luckyOdd.lastIndex] if (j > max || k > max) { throw IAE("At least one argument is too big") } for (num in luckyOdd) { if (num < j) continue if (num > k) break range.add(num) } println("Lucky numbers between $j and $k are:\n$range") } else { val max = luckyEven[luckyEven.lastIndex] if (j > max || k > max) { throw IAE("At least one argument is too big") } for (num in luckyEven) { if (num < j) continue if (num > k) break range.add(num) } println("Lucky even numbers between $j and $k are:\n$range") }
}
fun main(args: Array<String>) {
if (args.size !in 1..3) throw IAE("There must be between 1 and 3 command line arguments") filterLuckyOdd() filterLuckyEven() val j = args[0].toIntOrNull() if (j == null || j < 1) throw IAE("First argument must be a positive integer") if (args.size == 1) { printSingle(j, true); return }
if (args.size == 2) { val k = args[1].toIntOrNull() if (k == null) throw IAE("Second argument must be an integer") if (k >= 0) { if (j > k) throw IAE("Second argument can't be less than first") printRange(j, k, true) } else { val l = -k if (j > l) throw IAE("The second argument can't be less in absolute value than first") printBetween(j, l, true) } return }
var odd = if (args[2].toLowerCase() == "lucky") true else if (args[2].toLowerCase() == "evenlucky") false else throw IAE("Third argument is invalid")
if (args[1] == ",") { printSingle(j, odd) return }
val k = args[1].toIntOrNull() if (k == null) throw IAE("Second argument must be an integer or a comma")
if (k >= 0) { if (j > k) throw IAE("Second argument can't be less than first") printRange(j, k, odd) } else { val l = -k if (j > l) throw IAE("The second argument can't be less in absolute value than first") printBetween(j, l, odd) }
}</lang>
- Output:
$ java -jar lucky.jar 1 20 Lucky numbers 1 to 20 are: [1, 3, 7, 9, 13, 15, 21, 25, 31, 33, 37, 43, 49, 51, 63, 67, 69, 73, 75, 79] $ java -jar lucky.jar 1 20 evenLucky Lucky even numbers 1 to 20 are: [2, 4, 6, 10, 12, 18, 20, 22, 26, 34, 36, 42, 44, 50, 52, 54, 58, 68, 70, 76] $ java -jar lucky.jar 6000 -6100 Lucky numbers between 6000 and 6100 are: [6009, 6019, 6031, 6049, 6055, 6061, 6079, 6093] $ java -jar lucky.jar 6000 -6100 evenLucky Lucky even numbers between 6000 and 6100 are: [6018, 6020, 6022, 6026, 6036, 6038, 6050, 6058, 6074, 6090, 6092] $ java -jar lucky.jar 10000 , lucky Lucky number 10000 = 115591 $ java -jar lucky.jar 10000 , evenLucky Lucky even number 10000 = 111842
Perl
The module Perl6::GatherTake
emulates the Perl 6 gather/take syntax, and allows us to access values from what acts (mostly) like a lazy list.
<lang perl>use Perl6::GatherTake;
sub luck { my($a,$b) = @_;
gather {
my $i = $b; my(@taken,@rotor,$j);
take 0; # 0th index is a placeholder push @taken, take $a;
while () { for ($j = 0; $j < @rotor; $j++) { --$rotor[$j] or last; } if ($j < @rotor) { $rotor[$j] = $taken[$j+1]; } else { take $i; push @taken, $i; push @rotor, $i - @taken; } $i += 2; }
} }
- fiddle with user input
$j = shift || usage(); $k = shift || ','; $l = shift || 'lucky'; usage() unless $k =~ /,|-?\d+/; usage() unless $l =~ /^(even)?lucky$/i; sub usage { print "Args must be: j [,|k|-k] [lucky|evenlucky]\n" and exit }
- seed the iterator
my $lucky = $l =~ /^l/i ? luck(1,3) : luck(2,4);
- access values from 'lazy' list
if ($k eq ',') {
print $lucky->[$j]
} elsif ($k > $j) {
print $lucky->[$_] . ' ' for $j..$k
} elsif ($k < 0) {
while () { last if abs($k) < $lucky->[$i++] } # must first extend the array print join ' ', grep { $_ >= $j and $_ <= abs($k) } @$lucky
}
print "\n"</lang>
- Output:
$ ./lucky Args must be: j [,|k|-k] [lucky|evenlucky] $ ./lucky 20 , lucky 79 $ ./lucky 20 , evenlucky 76 $ ./lucky 1 20 1 3 7 9 13 15 21 25 31 33 37 43 49 51 63 67 69 73 75 79 $ ./lucky 1 20 evenlucky 2 4 6 10 12 18 20 22 26 34 36 42 44 50 52 54 58 68 70 76 $ ./lucky 6000 -6100 6009 6019 6031 6049 6055 6061 6079 6093 $ ./lucky 6000 -6100 evenLucky 6018 6020 6022 6026 6036 6038 6050 6058 6074 6090 6092 $ ./lucky 10000 115591 $ ./lucky 10000 , EVENLUCKY 111842
Perl 6
<lang perl6>sub luck(\a,\b) {
gather {
my @taken = take a; my @rotor; my $i = b;
loop { loop (my $j = 0; $j < @rotor; $j++) { --@rotor[$j] or last; } if $j < @rotor { @rotor[$j] = @taken[$j+1]; } else { push @taken, take $i; push @rotor, $i - @taken; } $i += 2; }
}
}
constant @lucky = luck(1,3); constant @evenlucky = luck(2,4);
subset Luck where m:i/^ 'even'? 'lucky' $/;
multi MAIN (Int $num where * > 0) {
say @lucky[$num-1];
}
multi MAIN (Int $num where * > 0, ',', Luck $howlucky = 'lucky') {
say @::(lc $howlucky)[$num-1];
}
multi MAIN (Int $first where * > 0, Int $last where * > 0, Luck $howlucky = 'lucky') {
say @::(lc $howlucky)[$first-1 .. $last - 1];
}
multi MAIN (Int $min where * > 0, Int $neg-max where * < 0, Luck $howlucky = 'lucky') {
say grep * >= $min, (@::(lc $howlucky) ...^ * > abs $neg-max);
}</lang>
- Output:
$ ./lucky Usage: ./lucky <num> ./lucky <num> , [<howlucky>] ./lucky <first> <last> [<howlucky>] ./lucky <min> <neg-max> [<howlucky>] $ ./lucky 20 , lucky 79 $ ./lucky 20 , evenlucky 76 $ ./lucky 1 20 1 3 7 9 13 15 21 25 31 33 37 43 49 51 63 67 69 73 75 79 $ ./lucky 1 20 evenlucky 2 4 6 10 12 18 20 22 26 34 36 42 44 50 52 54 58 68 70 76 $ ./lucky 6000 -6100 6009 6019 6031 6049 6055 6061 6079 6093 $ ./lucky 6000 -6100 evenLucky 6018 6020 6022 6026 6036 6038 6050 6058 6074 6090 6092 $ ./lucky 10000 115591 $ ./lucky 10000 , EVENLUCKY 111842
Phix
<lang Phix>constant luckyMax = 120000
sequence lucky
procedure filterLucky()
integer n = 2 while n<=length(lucky) do integer m = lucky[n], l = m-1 for k=m+1 to length(lucky) do if mod(k,m)!=0 then l += 1 lucky[l] = lucky[k] end if end for if l>=length(lucky) then exit end if lucky = lucky[1..l] n += 1 end while
end procedure
constant helptxt = """
argument(s) | what is displayed
===========================
j | jth lucky number j [,] lucky | jth lucky number j [,] evenLucky | jth even lucky number j k | jth through kth (inclusive) lucky numbers j k lucky | jth through kth (inclusive) lucky numbers j k evenLucky | jth through kth (inclusive) even lucky numbers j -k | all lucky numbers in the range j to k j -k lucky | all lucky numbers in the range j to k j -k evenLucky | all even lucky numbers in the range j to k
"""
procedure fatal(string msg)
puts(1,msg) puts(1,helptxt) {} = wait_key() abort(0)
end procedure
procedure main()
sequence cl = command_line() integer j,k,l,m,n bool single = true, range = true, odd = true if length(cl)=2 then
-- fatal("at least one argument must be supplied") -- (if preferred)
sequence tests = {"1 20", "1 20 evenLucky", "20 lucky", "20 evenLucky", "6000 -6100", "6000 -6100 evenLucky", "10000 lucky", "10000 evenLucky"} -- (done this way to exercise the real command line handling) if cl[1]=cl[2] then -- (compiled) cl = cl[1..1] elsif platform()=WINDOWS then -- (and interpreted) cl[1] = substitute(cl[1],"pw","p") -- (pw.exe -> p.exe) end if for i=1 to length(cl) do if find(' ',cl[i]) then cl[i] = sprintf("\"%s\"",{cl[i]}) end if end for for t=1 to length(tests) do string cmd = join(append(cl,tests[t]))
-- printf(1,"running %s\n",{cmd})
{} = system_exec(cmd) end for puts(1, "tests complete\n") {} = wait_key() else cl = cl[3..$] -- ({1,2} are {interperter,source} or {exe,exe})
-- -- Allow eg "lucky j , evenLucky" to be == "lucky j evenLucky" -- if length(cl)=3 and cl[2]="," then cl[2..2] = {} end if
for i=1 to length(cl) do string cli = cl[i] if cli[1]<='9' then -- (includes '-') sequence d = scanf(cl[i],"%d") if length(d)!=1 then fatal("unrecognised "&cli) end if if i>2 then fatal("too many numbers") end if n = d[1][1] if i=1 then if n<1 then fatal("first argument must be a positive integer") end if j = n else single = false if n<0 then range = false n = -n end if if n<j then fatal("second argument cannot be less than first") end if k = n end if else l = find(cli,{"lucky","evenLucky"}) if l=0 then fatal("unrecognised "&cli) end if if i!=length(cl) then fatal(cli&" must be last parameter") end if odd = (l=1) end if end for lucky = tagset(luckyMax,2-odd,2) filterLucky() printf(1,"Output when args are %s\n",{join(cl)}) string even = iff(odd?"":"even ") if single then if j>length(lucky) then fatal(sprintf("the argument, %d, is too big", j)) end if printf(1,"Lucky %snumber %d = %d\n",{even,j, lucky[j]}) elsif range then if k>length(lucky) then fatal(sprintf("the argument, %d, is too big", k)) end if printf(1,"Lucky %snumbers %d to %d are: %s\n",{even,j,k,sprint(lucky[j..k])}) else if j>lucky[$] then fatal("start of range is too big") elsif k>lucky[$] then fatal("end of range is too big") end if m = abs(binary_search(j,lucky)) n = binary_search(k,lucky) if n<0 then n = -n-1 end if printf(1,"Lucky %snumbers between %d and %d are: %s\n", {even,j,k,sprint(lucky[m..n])}) end if end if
end procedure main()</lang>
- Output:
Output when args are 1 20 Lucky numbers 1 to 20 are: {1,3,7,9,13,15,21,25,31,33,37,43,49,51,63,67,69,73,75,79} Output when args are 1 20 evenLucky Lucky even numbers 1 to 20 are: {2,4,6,10,12,18,20,22,26,34,36,42,44,50,52,54,58,68,70,76} Output when args are 20 lucky Lucky number 20 = 79 Output when args are 20 evenLucky Lucky even number 20 = 76 Output when args are 6000 -6100 Lucky numbers between 6000 and 6100 are: {6009,6019,6031,6049,6055,6061,6079,6093} Output when args are 6000 -6100 evenLucky Lucky even numbers between 6000 and 6100 are: {6018,6020,6022,6026,6036,6038,6050,6058,6074,6090,6092} Output when args are 10000 lucky Lucky number 10000 = 115591 Output when args are 10000 evenLucky Lucky even number 10000 = 111842 tests complete
PicoLisp
<lang PicoLisp>(off *Even)
(de nn (Lst N)
(seek '((L) (when (car L) (=0 (dec 'N))) ) Lst ) )
(de lucky (B)
(let Lst (range (if *Even 2 1) B 2) (for A (cdr Lst) (for (L (nn Lst A) L (nn (cdr L) A)) (set L) ) ) (filter bool Lst) ) )
(argv . *Argv) # without validations (when (= "evenLucky" (last *Argv)) (on *Even)) (setq *Lst (lucky 7000)) (let (A (format (car *Argv)) B (format (cadr *Argv)))
(println (if (lt0 B) (filter '((N) (<= A N (abs B))) *Lst) (head B (nth *Lst A)) ) ) )</lang>
- Output:
$ pil ./lucky.l 1 20 (1 3 7 9 13 15 21 25 31 33 37 43 49 51 63 67 69 73 75 79) $ pil ./lucky.l 1 20 evenLucky (2 4 6 10 12 18 20 22 26 34 36 42 44 50 52 54 58 68 70 76) $ pil ./lucky.l 6000 -6100 (6009 6019 6031 6049 6055 6061 6079 6093) $ pil ./lucky.l 6000 -6100 evenLucky (6018 6020 6022 6026 6036 6038 6050 6058 6074 6090 6092)
Python
The generator <lang python>from __future__ import print_function
def lgen(even=False, nmax=1000000):
start = 2 if even else 1 n, lst = 1, list(range(start, nmax + 1, 2)) lenlst = len(lst) yield lst[0] while n < lenlst and lst[n] < lenlst: yield lst[n] n, lst = n + 1, [j for i,j in enumerate(lst, 1) if i % lst[n]] lenlst = len(lst) # drain for i in lst[n:]: yield i</lang>
The argument handler <lang python>from itertools import islice import sys, re
class ArgumentError(Exception):
pass
def arghandler(argstring):
match_obj = re.match( r"""(?mx) (?: (?P<SINGLE> (?: ^ (?P<SINGLEL> \d+ ) (?: | \s , \s lucky ) \s* $ ) |(?: ^ (?P<SINGLEE> \d+ ) (?: | \s , \s evenLucky ) \s* $ ) ) |(?P<KTH> (?: ^ (?P<KTHL> \d+ \s \d+ ) (?: | \s lucky ) \s* $ ) |(?: ^ (?P<KTHE> \d+ \s \d+ ) (?: | \s evenLucky ) \s* $ ) ) |(?P<RANGE> (?: ^ (?P<RANGEL> \d+ \s -\d+ ) (?: | \s lucky ) \s* $ ) |(?: ^ (?P<RANGEE> \d+ \s -\d+ ) (?: | \s evenLucky ) \s* $ ) ) )""", argstring) if match_obj: # Retrieve group(s) by name SINGLEL = match_obj.group('SINGLEL') SINGLEE = match_obj.group('SINGLEE') KTHL = match_obj.group('KTHL') KTHE = match_obj.group('KTHE') RANGEL = match_obj.group('RANGEL') RANGEE = match_obj.group('RANGEE') if SINGLEL: j = int(SINGLEL) assert 0 < j < 10001, "Argument out of range" print("Single %i'th lucky number:" % j, end=' ') print( list(islice(lgen(), j-1, j))[0] ) elif SINGLEE: j = int(SINGLEE) assert 0 < j < 10001, "Argument out of range" print("Single %i'th even lucky number:" % j, end=' ') print( list(islice(lgen(even=True), j-1, j))[0] ) elif KTHL: j, k = [int(num) for num in KTHL.split()] assert 0 < j < 10001, "first argument out of range" assert 0 < k < 10001 and k > j, "second argument out of range" print("List of %i ... %i lucky numbers:" % (j, k), end=' ') for n, luck in enumerate(lgen(), 1): if n > k: break if n >=j: print(luck, end = ', ') print() elif KTHE: j, k = [int(num) for num in KTHE.split()] assert 0 < j < 10001, "first argument out of range" assert 0 < k < 10001 and k > j, "second argument out of range" print("List of %i ... %i even lucky numbers:" % (j, k), end=' ') for n, luck in enumerate(lgen(even=True), 1): if n > k: break if n >=j: print(luck, end = ', ') print() elif RANGEL: j, k = [int(num) for num in RANGEL.split()] assert 0 < j < 10001, "first argument out of range" assert 0 < -k < 10001 and -k > j, "second argument out of range" k = -k print("List of lucky numbers in the range %i ... %i :" % (j, k), end=' ') for n in lgen(): if n > k: break if n >=j: print(n, end = ', ') print() elif RANGEE: j, k = [int(num) for num in RANGEE.split()] assert 0 < j < 10001, "first argument out of range" assert 0 < -k < 10001 and -k > j, "second argument out of range" k = -k print("List of even lucky numbers in the range %i ... %i :" % (j, k), end=' ') for n in lgen(even=True): if n > k: break if n >=j: print(n, end = ', ') print() else: raise ArgumentError( Error Parsing Arguments! Expected Arguments of the form (where j and k are integers): j # Jth lucky number j , lucky # Jth lucky number j , evenLucky # Jth even lucky number # j k # Jth through Kth (inclusive) lucky numbers j k lucky # Jth through Kth (inclusive) lucky numbers j k evenLucky # Jth through Kth (inclusive) even lucky numbers # j -k # all lucky numbers in the range j --? |k| j -k lucky # all lucky numbers in the range j --? |k| j -k evenLucky # all even lucky numbers in the range j --? |k| )
if __name__ == '__main__':
arghandler(' '.join(sys.argv[1:]))</lang>
- Output:
# Output when arguments are: 1 20 lucky List of 1 ... 20 lucky numbers: 1, 3, 7, 9, 13, 15, 21, 25, 31, 33, 37, 43, 49, 51, 63, 67, 69, 73, 75, 79, # Output when arguments are: 1 20 evenLucky List of 1 ... 20 even lucky numbers: 2, 4, 6, 10, 12, 18, 20, 22, 26, 34, 36, 42, 44, 50, 52, 54, 58, 68, 70, 76, # Output when arguments are: 6000 -6100 lucky List of lucky numbers in the range 6000 ... 6100 : 6009, 6019, 6031, 6049, 6055, 6061, 6079, 6093, # Output when arguments are: 6000 -6100 evenLucky List of even lucky numbers in the range 6000 ... 6100 : 6018, 6020, 6022, 6026, 6036, 6038, 6050, 6058, 6074, 6090, 6092, # Output when arguments are: 10000 Single 10000'th lucky number: 115591 # Output when arguments are: 10000 , evenLucky Single 10000'th even lucky number: 111842
REXX
This REXX version does extra error checking for the arguments. <lang REXX>/*REXX program displays lucky or evenLucky integers (numbers or a number range).*/ parse arg bot top func _ . /*obtain required & optional arguments.*/ if func== then func='lucky' /*Not specified? Then use the default.*/ s=left('s', bot\==top & top\==",") /*plural results (or maybe not plural).*/ say func 'number's":" bot top '───►' $lucky(bot, top, func, _) exit /*stick a fork in it, we're all done. */ /*──────────────────────────────────────────────────────────────────────────────────────*/ $lucky: arg x,y,f,?; if y== | y=="," then y=x /*obtain some arguments; set Y.*/
#=0; $=; ny=y<0 /*set variable NOY: value range*/ if f== then f='LUCKY'; lucky= (f=="LUCKY") /*assume LUCKY if omitted. */ if f\=='LUCKY' & f\=='EVENLUCKY' then return 'function not valid: ' f if arg()>3 & ?\= then return "too many arguments entered: " ? if x= then return "1st argument is missing." if x<1 then return "1st argument isn't a positive integer: " x if \datatype(x,'W') then return "1st argument isn't an integer: " x if \datatype(y,'W') then return "2nd argument isn't an integer: " y if x>ay then return "2nd argument is less than 1st arg." ay=abs(y); yL=ay; if y>0 then yL=y*10+y+y /*adjust the upper Y limit. */ /* [↓] build LUCKY | EVENLUCKY*/ do j=1 until j>=yL /*construct list pos. integers.*/ if j//2==(\lucky) then iterate /*EVENLUCKY? Use only even ints*/
if lucky then if (j+1)//6==0 then iterate /*prune if mod 6 ≡ zero.*/ else nop /*balance the IF-THEN logic.*/ else if j //8==0 then iterate /*prune next if mod 8 ≡ zero.*/ #=#+1 /*bump the counter of numbers. */ $=$ j /*append integer to the $ list.*/ end /*j*/ q=0 do p=3 until q==; q=word($,p) /*start to prune integer list.*/ if q># then leave /*if integer is too large, stop*/ do j=#%q*q by -q to q /*elide every Qth integer. */ $=delword($, j, 1) /*delete a particular number. */ #=#-1 /*decrease the integer count. */ end /*j*/ /*delete from the right side. */ end /*p*/ @.= do k=1; parse var $ q $; if q== then leave; @.k=q; end /*k*/ @.0=k-1 do m=1 for # /*restrict the found integers. */ if (\ny & (m<x | m>ay)) | (ny & (@.m<x | @.m>ay)) then @.m= end /*m*/ /* [↑] a list of #s or a range*/ _= do b=1 for @.0; _=_ @.b; end /*b*/ /*construct a list of integers.*/ return space(_) /*remove superfluous blanks. */</lang>
output when the input is: 1 20 lucky
lucky numbers: 1 20 ───► 1 3 7 9 13 15 21 25 31 33 37 43 49 51 63 67 69 73 75 79
output when the input is: 1 20 evenLucky
evenLucky numbers: 1 20 ───► 2 4 6 10 12 18 20 22 26 34 36 42 44 50 52 54 58 68 70 76
output when the input is: 6000 -6100 lucky
lucky numbers: 6000 -6100 ───► 6009 6019 6031 6049 6055 6061 6079 6093
output when the input is: 6000 -6100 venLucky
evenLucky numbers: 6000 -6100 ───► 6018 6020 6022 6026 6036 6038 6050 6058 6074 6090 6092
output when the input is: 10000
lucky number: 10000 ───► 115591
output when the input is: 10000 , evenLucky
evenLucky number: 10000 ───► 111842
Ring
<lang ring>
- Project : Lucky and even lucky numbers
lucky = list(50) dellucky = [] for n = 1 to 50
lucky[n] = 2*n-1
next see "the first 20 lucky numbers:" + nl luckynumbers(lucky) showarray(lucky) see nl
lucky = list(50) dellucky = [] for n = 1 to 50
lucky[n] = 2*n
next see "the first 20 even lucky numbers:" + nl luckynumbers(lucky) showarray(lucky) see nl
lucky = list(20000) dellucky = [] for n = 1 to 10000
lucky[n] = 2*n-1
next see "lucky numbers between 6,000 and 6,100:" + nl luckynumbers2(lucky) showarray2(lucky) see nl
lucky = list(20000) dellucky = [] for n = 1 to 10000
lucky[n] = 2*n
next see "even lucky numbers between 6,000 and 6,100:" + nl luckynumbers2(lucky) showarray2(lucky) see nl
func luckynumbers(lucky)
for n = 2 to len(lucky) dellucky = [] for m = lucky[n] to len(lucky) step lucky[n] add(dellucky, m) next for p = len(dellucky) to 1 step -1 del(lucky, dellucky[p]) next next
func luckynumbers2(lucky)
for n = 2 to len(lucky) dellucky = [] for m = lucky[n] to len(lucky) step lucky[n] add(dellucky, m) next for p = len(dellucky) to 1 step -1 del(lucky, dellucky[p]) next if lucky[n] >= 6100 exit ok
next
func showarray(vect)
see "[" svect = "" for n = 1 to 20 svect = svect + vect[n] + ", " next svect = left(svect, len(svect) - 2) see svect see "]" + nl
func showarray2(vect)
see "[" svect = "" for n = 1 to len(vect) if vect[n] >= 6000 and vect[n] <= 6100 svect = svect + vect[n] + ", " ok next svect = left(svect, len(svect) - 2) see svect see "]" + nl
</lang> Output:
the first 20 lucky numbers: [1, 3, 7, 9, 13, 15, 21, 25, 31, 33, 37, 43, 49, 51, 63, 67, 69, 73, 75, 79] the first 20 even lucky numbers: [2, 4, 6, 10, 12, 18, 20, 22, 26, 34, 36, 42, 44, 50, 52, 54, 58, 68, 70, 76] lucky numbers between 6,000 and 6,100: [6009, 6019, 6031, 6049, 6055, 6061, 6079, 6093] even lucky numbers between 6,000 and 6,100: [6018, 6020, 6022, 6026, 6036, 6038, 6050, 6058, 6074, 6090, 6092]
Ruby
<lang ruby>def generator(even=false, nmax=1000000)
start = even ? 2 : 1 Enumerator.new do |y| n = 1 ary = [0] + (start..nmax).step(2).to_a # adds [0] to revise the 0 beginnings. y << ary[n] while (m = ary[n+=1]) < ary.size y << m (m...ary.size).step(m){|i| ary[i]=nil} ary.compact! # remove nil end # drain ary[n..-1].each{|i| y << i} raise StopIteration end
end
def lucky(argv)
j, k = argv[0].to_i, argv[1].to_i mode = /even/i=~argv[2] ? :'even lucky' : :lucky seq = generator(mode == :'even lucky') ord = ->(n){"#{n}#{(n%100).between?(11,19) ? 'th' : %w[th st nd rd th th th th th th][n%10]}"} if k.zero? puts "#{ord[j]} #{mode} number: #{seq.take(j).last}" elsif 0 < k puts "#{ord[j]} through #{ord[k]} (inclusive) #{mode} numbers", " #{seq.take(k)[j-1..-1]}" else k = -k ary = [] loop do case num=seq.next when 1...j when j..k then ary << num else break end end puts "all #{mode} numbers in the range #{j}..#{k}", " #{ary}" end
end
if __FILE__ == $0
lucky(ARGV)
end</lang>
- Output:
C:\>ruby lucky.rb 1 20 1st through 20th (inclusive) lucky numbers [1, 3, 7, 9, 13, 15, 21, 25, 31, 33, 37, 43, 49, 51, 63, 67, 69, 73, 75, 79] C:\>ruby lucky.rb 1 20 evenLucky 1st through 20th (inclusive) even lucky numbers [2, 4, 6, 10, 12, 18, 20, 22, 26, 34, 36, 42, 44, 50, 52, 54, 58, 68, 70, 76] C:\>ruby lucky.rb 6000 -6100 Lucky all lucky numbers in the range 6000..6100 [6009, 6019, 6031, 6049, 6055, 6061, 6079, 6093] C:\>ruby lucky.rb 6000 -6100 evenLucky all even lucky numbers in the range 6000..6100 [6018, 6020, 6022, 6026, 6036, 6038, 6050, 6058, 6074, 6090, 6092] C:\>ruby lucky.rb 10000 10000th lucky number: 115591 C:\>ruby lucky.rb 10000 , EVENLUCKY 10000th even lucky number: 111842
Tcl
<lang tcl>#!/usr/bin/env tclsh8.6 package require Tcl 8.6
proc lgen {{even false} {nmax 200000}} {
coroutine lgen.[incr ::lgen] apply {{start nmax} {
set n 1 for {set i $start} {$i <= $nmax+1} {incr i 2} {lappend lst $i} yield [info coroutine] yield [lindex $lst 0] while {$n < [llength $lst] && [lindex $lst $n] < [llength $lst]} { yield [lindex $lst $n] set lst [set i 0;lmap j $lst { if {[incr i] % [lindex $lst $n]} {set j} else continue }] incr n } foreach i [lrange $lst $n end] { yield $i }
}} [expr {$even ? 2 : 1}] $nmax
}
proc collectIndices {generator from to} {
set result {} for {set i 0} {$i <= $to} {incr i} {
set n [$generator] if {$i >= $from} {lappend result $n}
} rename $generator {} return $result
} proc collectValues {generator from to} {
set result {} while 1 {
set n [$generator] if {$n > $to} break if {$n >= $from} {lappend result $n}
} rename $generator {} return $result
}
if {$argc<1||$argc>3} {
puts stderr "wrong # args: should be \"$argv0 from ?to? ?evenOdd?\"" exit 1
} lassign $argv from to evenOdd if {$argc < 3} {set evenOdd lucky} if {$argc < 2} {set to ,} if {![string is integer -strict $from] || $from < 1} {
puts stderr "\"from\" must be positive integer" exit 1
} elseif {$to ne "," && (![string is integer -strict $to] || $to == 0)} {
puts stderr "\"to\" must be positive integer or comma" exit 1
} elseif {[set evenOdd [string tolower $evenOdd]] ni {lucky evenlucky}} {
puts stderr "\"evenOdd\" must be \"lucky\" or \"evenLucky\"" exit 1
} set l [lgen [expr {$evenOdd eq "evenlucky"}]] set evenOdd [lindex {"lucky" "even lucky"} [expr {$evenOdd eq "evenlucky"}]] if {$to eq ","} {
puts "$from'th $evenOdd number = [collectIndices $l [incr from -1] $from]"
} elseif {$to < 0} {
set to [expr {-$to}] puts "all $evenOdd numbers from $from to $to: [join [collectValues $l $from $to] ,]"
} else {
puts "$from'th to $to'th $evenOdd numbers: [join [collectIndices $l [incr from -1] [incr to -1]] ,]"
}</lang>
- Output:
bash$ lucky.tcl 1 20 1'th to 20'th lucky numbers: 1,3,7,9,13,15,21,25,31,33,37,43,49,51,63,67,69,73,75,79 bash$ lucky.tcl 1 20 evenLucky 1'th to 20'th even lucky numbers: 2,4,6,10,12,18,20,22,26,34,36,42,44,50,52,54,58,68,70,76 bash$ lucky.tcl 6000 -6100 all lucky numbers from 6000 to 6100: 6009,6019,6031,6049,6055,6061,6079,6093 bash$ lucky.tcl 6000 -6100 evenLucky all even lucky numbers from 6000 to 6100: 6018,6020,6022,6026,6036,6038,6050,6058,6074,6090,6092 bash$ lucky.tcl 10000 10000'th lucky number = 115591 bash$ lucky.tcl 10000 , evenLucky 10000'th even lucky number = 111842
zkl
The lucky number generator works by chaining filters to a even or odd infinite sequence. So it acts like a sieve as each starting number percolates through the filters. It also means there are lots and lots of filters, which doesn't scale well but works for the examples. <lang zkl>fcn lgen(a){
ns,idx:=[a..*,2],2; vm.yield(ns.next()); while(1){ n:=ns.next(); vm.yield(n); ns=ns.tweak(skipper.fp1(n,Ref(idx+=1))); // tack on another filter }
} fcn skipper(n,skp,cnt){ z:=cnt.inc(); if(z%skp==0) Void.Skip else n }</lang> The command line is a bit funky (by Unix standards) so we just hard code it and use exceptions (such as trying to convert "foo" to int) to show the options. <lang zkl>cmdLineArgs,j,k,start:=vm.arglist,Void,Void,1; try{
j=cmdLineArgs[0].toInt(); na:=cmdLineArgs.len(); if(na>1){ if(cmdLineArgs[1]==",") start=cmdLineArgs[2][0].toLower()=="e" and 2 or 1; else{
k=cmdLineArgs[1].toInt(); if(na>2) start=cmdLineArgs[2][0].toLower()=="e" and 2 or 1;
} }
}catch{
fcn options{ "args: j | j , [even]lucky | j k [even]lucky | j -k [even]lucky" .println(); System.exit(1); }()
} luckies:=Utils.Generator(lgen,start); try{
if(Void==k) luckies.drop(j-1).next().println(); else{ if(k>0) luckies.drop(j-1).walk(k-j+1).println(); else{ k=-k;
while((n:=luckies.next())<j){} luckies.push(n); luckies.pump(List,'wrap(n){ n<=k and n or Void.Stop }).println();
} }
}catch(TheEnd){ options() }</lang>
- Output:
$ zkl lucky args: j | j , [even]lucky | j k [even]lucky | j -k [even]lucky $ zkl lucky 1 20 L(1,3,7,9,13,15,21,25,31,33,37,43,49,51,63,67,69,73,75,79) $ zkl lucky 1 20 evenLucky L(2,4,6,10,12,18,20,22,26,34,36,42,44,50,52,54,58,68,70,76) $ zkl lucky 6000 -6100 L(6009,6019,6031,6049,6055,6061,6079,6093) $ zkl lucky 6000 -6100 Even L(6018,6020,6022,6026,6036,6038,6050,6058,6074,6090,6092) $ zkl lucky 10000 115591 $ zkl lucky 10000 , evenLucky 111842 $ zkl lucky 6000 -5000 L() $ zkl lucky 4 2 args: j | j , [even]lucky | j k [even]lucky | j -k [even]lucky