WIP: implement part 2

src/days/day11.zig

@@ -5,16 +5,19 @@ pub const title = "Day 11: Reactor";
 pub fn run(allocator: std.mem.Allocator) !void {
     const input = @embedFile("./input/day11.txt");
     //const input =
-    //    \\aaa: you hhh
-    //    \\you: bbb ccc
-    //    \\bbb: ddd eee
-    //    \\ccc: ddd eee fff
-    //    \\ddd: ggg
-    //    \\eee: out
-    //    \\fff: out
+    //    \\svr: aaa bbb
+    //    \\aaa: fft
+    //    \\fft: ccc
+    //    \\bbb: tty
+    //    \\tty: ccc
+    //    \\ccc: ddd eee
+    //    \\ddd: hub
+    //    \\hub: fff
+    //    \\eee: dac
+    //    \\dac: fff
+    //    \\fff: ggg hhh
     //    \\ggg: out
-    //    \\hhh: ccc fff iii
-    //    \\iii: out
+    //    \\hhh: out
     //    ;
 
     var lines = std.mem.tokenizeScalar(u8, input, '\n');
@@ -47,7 +50,7 @@ pub fn run(allocator: std.mem.Allocator) !void {
     }
 
     var paths_to_out: usize = 0;
-    visitOutputs("you", devices, &paths_to_out);
+    visitOutputs("svr", devices, &paths_to_out, false, false);
 
     var buffer: [8]u8 = undefined;
     var stdout_writer = std.fs.File.stdout().writer(&buffer);
@@ -62,14 +65,26 @@ fn visitOutputs(
     start: []const u8,
     devices: std.StringHashMap([][]const u8),
     paths_to_out: *usize,
+    visited_fft: bool,
+    visited_dac: bool,
 ) void {
     const device = devices.get(start);
     if (device) |outputs| {
         for (outputs) |output| {
             if (std.mem.eql(u8, output, "out")) {
-                paths_to_out.* += 1;
+                std.debug.print("found out! (fft = {any}, dac = {any})\n", .{visited_fft, visited_dac});
+                if (visited_fft and visited_dac) {
+                    std.debug.print("visited fft and dac\n", .{});
+                    paths_to_out.* += 1;
+                }
+            } else if (std.mem.eql(u8, output, "fft")) {
+                std.debug.print("found fft!\n", .{});
+                visitOutputs(output, devices, paths_to_out, true, visited_dac);
+            } else if (std.mem.eql(u8, output, "dac")) {
+                std.debug.print("found dac!\n", .{});
+                visitOutputs(output, devices, paths_to_out, visited_fft, true);
             } else {
-                visitOutputs(output, devices, paths_to_out);
+                visitOutputs(output, devices, paths_to_out, visited_fft, visited_dac);
             }
         }
     } else {