Merge pull request #3607 from seaker/master

challenge 101, Feng Chang's Raku solutions

2 files changed, 31 insertions, 0 deletions

diff --git a/challenge-096/feng-chang/ch-1.raku b/challenge-096/feng-chang/ch-1.raku
new file mode 100755
index 0000000000..a8271c123a
--- /dev/null
+++ b/challenge-096/feng-chang/ch-1.raku
@@ -0,0 +1,4 @@
+#!/bin/env raku
+
+multi MAIN(Str:D $S) { put $S.words.reverse.join(' ') }
+multi MAIN(*@S)      { MAIN(@S.join(' ')) }
diff --git a/challenge-096/feng-chang/ch-2.raku b/challenge-096/feng-chang/ch-2.raku
new file mode 100755
index 0000000000..a84a74b7d7
--- /dev/null
+++ b/challenge-096/feng-chang/ch-2.raku
@@ -0,0 +1,27 @@
+#!/bin/env raku
+
+sub levenshtein-distance(Str:D $s, Str:D $t) {
+    my @S = $s.comb; my $m = @S.elems;
+    my @T = $t.comb; my $n = @T.elems;
+
+    my Array @a = (0 xx ($m+1)).Array xx ($n+1);
+    @a[0;1..$m] = 1..$m;
+    @a[1..$n;0] = 1..$n;
+
+	for ^$n -> $j {
+        for ^@S.elems -> $i {
+            my $subst-cost = @S[$i] eq @T[$j] ?? 0 !! 1;
+
+            @a[$j+1;$i+1] = min(
+                @a[$j;$i+1] + 1,            # deletion
+                @a[$j+1;$i] + 1,            # insertion
+                @a[$j;$i] + $subst-cost     # substitution
+            );
+        }
+    }
+ 
+    @a[$n;$m], @a.item;
+}
+
+put levenshtein-distance('kitten', 'sitting')[0];
+put levenshtein-distance('Saturday', 'Sunday')[0];