first few days

3/1.pl

@@ -0,0 +1,39 @@
+#!/usr/bin/perl
+
+use strict;
+
+chomp (my @data = <STDIN>);
+my %seen;
+
+foreach my $line (@data) {
+    # #1 @ 1,3: 4x4
+    #print $line . "\n";
+    my ($id, $sx, $sy, $w, $h) = ($line =~ m/#(\d+) @ (\d+),(\d+): (\d+)x(\d+)/);
+
+    foreach my $r (expand_area($sx, $sy, $w, $h)) {
+        #print "A: $r\n";
+        $seen{$r}++
+    }
+
+}
+
+my $count = 0;
+foreach my $k (keys %seen) {
+    #print "F: $k $seen{$k}\n";
+    if ($seen{$k} > 1) {
+        $count++
+    }
+}
+print $count . "\n";
+
+sub expand_area ($$$$) {
+    my @r;
+    my ($sx, $sy, $w, $h) = @_;
+    for (my $i = 0; $i < $w; $i++) {
+        for (my $j = 0; $j < $h; $j++) {
+            my $s = (($sx+$i) . "," . ($sy+$j));
+            push @r, $s;
+        }
+    }
+    return @r;
+}