Merge pull request #9685 from Util/c258

Add TWC 258 solutions by Bruce Gray, in Raku, Perl, and Java.

6 files changed, 159 insertions, 0 deletions

diff --git a/challenge-258/bruce-gray/java/ch-1.java b/challenge-258/bruce-gray/java/ch-1.java
new file mode 100644
index 0000000000..b60b8fcdf4
--- /dev/null
+++ b/challenge-258/bruce-gray/java/ch-1.java
@@ -0,0 +1,34 @@
+// java java/ch-1.java
+import java.util.List;
+public class ch_1 {
+
+
+    static long task1 ( List<Integer> ns ) {
+        return ns.stream()
+                 .filter(n -> n.toString().length() % 2 == 0)
+                 .count();
+    }
+
+
+    // Test harness
+    static int test_number = 1;
+    static void  plan ( Integer count ) { System.out.printf("1..%d\n", count); }
+    static boolean is ( long got, long expected, String desc ) {
+        boolean ret = got == expected;
+        System.out.printf("%s %d - %s\n", (ret ? "ok" : "not ok"), test_number++, desc);
+        return ret;
+    }
+    public static void main(String[] args) {
+        record Testcase ( int expected, List<Integer> inputs ) {}
+
+        List<Testcase> tst = List.of(
+            new Testcase( 3, List.of(  10, 1,   111,  24, 1000 ) ),
+            new Testcase( 0, List.of( 111, 1, 11111            ) ),
+            new Testcase( 1, List.of(   2, 8,  1024, 256       ) )
+        );
+        plan(tst.size());
+        for (Testcase t : tst) {
+            is( task1(t.inputs), t.expected, t.inputs.toString() );
+        }
+    }
+}
diff --git a/challenge-258/bruce-gray/java/ch-2.java b/challenge-258/bruce-gray/java/ch-2.java
new file mode 100644
index 0000000000..f7f9036d89
--- /dev/null
+++ b/challenge-258/bruce-gray/java/ch-2.java
@@ -0,0 +1,41 @@
+// java java/ch-2.java
+import java.util.List;
+import java.util.stream.IntStream;
+import java.util.stream.Collectors;
+public class ch_2 {
+
+
+    static int task2 ( Integer k, List<Integer> ns ) {
+        Integer[] ints = ns.toArray(new Integer[0]);
+
+        return IntStream.range(0, ints.length)
+            .filter(i -> Integer.bitCount(i) == k)
+            .mapToObj(i -> ints[i])
+            .collect(Collectors.summingInt(Integer::intValue));
+    }
+
+
+
+    // Test harness
+    static int test_number = 1;
+    static void  plan ( Integer count ) { System.out.printf("1..%d\n", count); }
+    static boolean is ( Integer got, Integer expected, String desc ) {
+        boolean ret = got == expected;
+        System.out.printf("%s %d - %s\n", (ret ? "ok" : "not ok"), test_number++, desc);
+        return ret;
+    }
+    public static void main(String[] args) {
+        record Testcase ( Integer expected, Integer in_k, List<Integer> in_nums ) {}
+
+        List<Testcase> tst = List.of(
+            new Testcase( 17, 1, List.of(2, 5, 9, 11, 3) ),
+            new Testcase( 11, 2, List.of(2, 5, 9, 11, 3) ),
+            new Testcase(  2, 0, List.of(2, 5, 9, 11, 3) )
+        );
+        plan(tst.size());
+        for (Testcase t : tst) {
+            is( task2(t.in_k, t.in_nums), t.expected, "k=" + t.in_k);
+        }
+
+    }
+}
diff --git a/challenge-258/bruce-gray/perl/ch-1.pl b/challenge-258/bruce-gray/perl/ch-1.pl
new file mode 100644
index 0000000000..98ab3129d5
--- /dev/null
+++ b/challenge-258/bruce-gray/perl/ch-1.pl
@@ -0,0 +1,16 @@
+use v5.36;
+sub task1 ( @ns ) {
+    return 0+grep { length(abs $_) % 2 == 0 } @ns;
+}
+
+
+my @tests = (
+    [ 3, [  10, 1,   111,  24, 1000 ] ],
+    [ 0, [ 111, 1, 11111            ] ],
+    [ 1, [   2, 8,  1024, 256       ] ],
+);
+use Test::More; plan tests => 0+@tests;
+for (@tests) {
+    my ($expected, $in) = @{$_};
+    is task1(@{$in}), $expected;
+}
diff --git a/challenge-258/bruce-gray/perl/ch-2.pl b/challenge-258/bruce-gray/perl/ch-2.pl
new file mode 100644
index 0000000000..851d62d479
--- /dev/null
+++ b/challenge-258/bruce-gray/perl/ch-2.pl
@@ -0,0 +1,22 @@
+use v5.36;
+use List::Util qw<sum>;
+
+sub pop_count ($n) { sprintf( '%b', $n ) =~ tr/1// }
+
+sub task2 ( $k, @ns ) {
+    my @wanted_keys = grep { pop_count($_) == $k } keys @ns;
+
+    return sum @ns[ @wanted_keys ];
+}
+
+
+my @tests = (
+    [ 17, 1, [2, 5, 9, 11, 3] ],
+    [ 11, 2, [2, 5, 9, 11, 3] ],
+    [  2, 0, [2, 5, 9, 11, 3] ],
+);
+use Test::More; plan tests => 0+@tests;
+for (@tests) {
+    my ($expected, $in_k, $in_ints) = @{$_};
+    is task2($in_k, @{$in_ints}), $expected;
+}
diff --git a/challenge-258/bruce-gray/raku/ch-1.raku b/challenge-258/bruce-gray/raku/ch-1.raku
new file mode 100644
index 0000000000..c11d9222a8
--- /dev/null
+++ b/challenge-258/bruce-gray/raku/ch-1.raku
@@ -0,0 +1,13 @@
+sub task1 ( @ns --> UInt ) {
+    return +grep { .abs.chars %% 2 }, @ns;
+}
+
+
+use Test; plan +my @tests =
+    ( 3, (  10, 1,   111,  24, 1000 ) ),
+    ( 0, ( 111, 1, 11111            ) ),
+    ( 1, (   2, 8,  1024, 256       ) ),
+;
+for @tests -> ( $expected, @in ) {
+    is task1(@in), $expected;
+}
diff --git a/challenge-258/bruce-gray/raku/ch-2.raku b/challenge-258/bruce-gray/raku/ch-2.raku
new file mode 100644
index 0000000000..e20d65b1b3
--- /dev/null
+++ b/challenge-258/bruce-gray/raku/ch-2.raku
@@ -0,0 +1,33 @@
+sub pop-count { $^n.base(2).comb('1').elems }
+
+sub pop-count-fast ($n is copy) {
+    constant @bits_per_2bytes = [X+] (0,1) xx 16; # Bwaahaahaa!
+    my $c = 0;
+    while $n {
+        $c += @bits_per_2bytes[$n +& 0xFFFF];
+        $n +>= 16;
+    }
+    return $c;
+}
+
+sub task2 ( UInt $k, @ns --> UInt ) {
+    # More concise alternatives:
+    # return @ns.grep({ pop-count($++) == $k }).sum;
+    # return @ns.pairs.map({ .value if pop-count(.key) == $k }).sum;
+
+    my &pop-count-is-k = *.&pop-count == $k;
+
+    my @wanted_keys = @ns.keys.grep: &pop-count-is-k;
+
+    return @ns[ @wanted_keys ].sum;
+}
+
+
+use Test; plan +my @tests =
+    ( 17, 1, (2, 5, 9, 11, 3) ),
+    ( 11, 2, (2, 5, 9, 11, 3) ),
+    (  2, 0, (2, 5, 9, 11, 3) ),
+;
+for @tests -> ( $expected, $in_k, @in_ints ) {
+    is task2($in_k, @in_ints), $expected;
+}