raku/DFS: Add DFS implementation in raku, Add input 06

1 files changed, 69 insertions, 0 deletions

diff --git a/algorithms/raku/DFS.raku b/algorithms/raku/DFS.raku
new file mode 100644
index 0000000..4789ce9
--- /dev/null
+++ b/algorithms/raku/DFS.raku
@@ -0,0 +1,69 @@
+use Octans::Neighbors;
+
+subset File of Str where *.IO.f;
+
+# Cells as defined by fornax format.
+constant $PATH = '.';
+constant $BLOK = '#';
+constant $DEST = '$';
+constant $STRT = '^';
+constant $VIS = '-';
+constant $CUR = '@';
+constant $CURPATH = '~';
+
+sub MAIN(File $input) {
+    my @maze = $input.IO.lines.map(*.comb);
+    die "Inconsistent maze" unless [==] @maze.map(*.elems);
+
+    put "rows:{@maze.elems} cols:{@maze[0].elems}";
+    dfs(@maze, 0, 0);
+}
+
+sub dfs(
+    @maze, Int $y, Int $x, @visited?, @cur-path? --> Bool
+) {
+    # If @visited was not passed then mark the given cell as visited
+    # because it's the cell we're starting at.
+    @visited[$y][$x] = True unless @visited;
+    @cur-path[$y][$x] = True unless @cur-path;
+
+    # neighbor block loops over the neighbors of $y, $x.
+    neighbor: for neighbors(@maze, $y, $x).List.pick(*) -> $pos {
+        # Move on to next neighbor if we've already visited this one.
+        next neighbor if @visited[$pos[0]][$pos[1]];
+
+        # Printing Marker cells.
+        given @maze[$pos[0]][$pos[1]] {
+            when $DEST { print "|" }
+            when $BLOK { print "!" }
+        }
+
+        # Print the maze on every iteration.
+        for 0..@maze.end -> $j {
+            for 0..@maze[0].end -> $k {
+                if @maze[$j][$k] eq $STRT | $DEST {
+                    print @maze[$j][$k];
+                } else {
+                    if $j == $pos[0] and $k == $pos[1] {
+                        print "@";
+                    } else {
+                        print(
+                            @cur-path[$j][$k]
+                            ?? "~" !! @visited[$j][$k] ?? "-" !! @maze[$j][$k]
+                        );
+                    }
+                }
+            }
+        }
+        print "\n";
+
+        given @maze[$pos[0]][$pos[1]] {
+            when $DEST { exit; }
+            when $PATH|$STRT {
+                @visited[$pos[0]][$pos[1]] = @cur-path[$pos[0]][$pos[1]] = True;
+                dfs(@maze, $pos[0], $pos[1], @visited, @cur-path);
+                @cur-path[$pos[0]][$pos[1]] = False;
+            }
+        }
+    }
+}