- Added solutions by Matthew Neleigh.

- Added solutions by Laurent Rosenfeld.

2 files changed, 31 insertions, 0 deletions

diff --git a/challenge-248/laurent-rosenfeld/blog1.txt b/challenge-248/laurent-rosenfeld/blog1.txt
new file mode 100644
index 0000000000..252bb3dec4
--- /dev/null
+++ b/challenge-248/laurent-rosenfeld/blog1.txt
@@ -0,0 +1 @@
+https://blogs.perl.org/users/laurent_r/2023/12/perl-weekly-challenge-248-submatrix-sum.html
diff --git a/challenge-248/laurent-rosenfeld/raku/ch-2.raku b/challenge-248/laurent-rosenfeld/raku/ch-2.raku
new file mode 100644
index 0000000000..56c99eac9b
--- /dev/null
+++ b/challenge-248/laurent-rosenfeld/raku/ch-2.raku
@@ -0,0 +1,30 @@
+sub submatrix-sum (@in) {
+    my $max-row = @in.end;
+    my $max-col = @in[0].end;
+    my @result;
+    for 0..^$max-row -> $i {
+        my @row;
+        for 0..^$max-col -> $j {
+            push @row, @in[$i][$j] + @in[$i][$j+1] +
+                @in[$i+1][$j] + @in[$i+1][$j+1];
+        }
+        push @result, @row; # push doesn't flatten
+    }
+    return @result;
+}
+
+my @tests = [
+              [1,  2,  3,  4],
+              [5,  6,  7,  8],
+              [9, 10, 11, 12]
+            ],
+            [
+              [1, 0, 0, 0],
+              [0, 1, 0, 0],
+              [0, 0, 1, 0],
+              [0, 0, 0, 1]
+            ];
+for @tests -> @test {
+    print @test.gist, " => ";;
+    say submatrix-sum @test;
+}