Data commit

Task/Dice-game-probabilities/Perl/dice-game-probabilities.pl

@@ -0,0 +1,35 @@
+use List::Util qw(sum0 max);
+
+sub comb {
+    my ($s, $n) = @_;
+    $n || return (1);
+    my @r = (0) x ($n - max(@$s) + 1);
+    my @c = comb($s, $n - 1);
+    foreach my $i (0 .. $#c) {
+        $c[$i] || next;
+        foreach my $k (@$s) {
+            $r[$i + $k] += $c[$i];
+        }
+    }
+    return @r;
+}
+
+sub winning {
+    my ($s1, $n1, $s2, $n2) = @_;
+
+    my @p1 = comb($s1, $n1);
+    my @p2 = comb($s2, $n2);
+
+    my ($win, $loss, $tie) = (0, 0, 0);
+
+    foreach my $i (0 .. $#p1) {
+        $win  += $p1[$i] * sum0(@p2[0    .. $i - 1]);
+        $tie  += $p1[$i] * sum0(@p2[$i   .. $i    ]);
+        $loss += $p1[$i] * sum0(@p2[$i+1 .. $#p2  ]);
+    }
+    my $total = sum0(@p1) * sum0(@p2);
+    map { $_ / $total } ($win, $tie, $loss);
+}
+
+print '(', join(', ', winning([1 ..  4], 9, [1 .. 6], 6)), ")\n";
+print '(', join(', ', winning([1 .. 10], 5, [1 .. 7], 6)), ")\n";