First (unsuccessful) attempt at day 7.1.

2018/day07-1.go

@@ -0,0 +1,29 @@
+package main
+
+import (
+	"fmt"
+	"strings"
+
+	"internal/tree"
+	"internal/util"
+)
+
+func main() {
+	data := util.ReadInput()
+
+	// Build a tree of dependencies.
+	root := tree.BuildDependencyTree(data)
+
+	// Walk the tree and determine the correct ordering.
+	order := tree.FindOrder(root)
+
+	output := strings.Builder{}
+	for _, node := range order {
+		if node.Name == 0 {
+			continue
+		}
+
+		output.WriteRune(node.Name)
+	}
+	fmt.Println(output.String())
+}