diff --git a/03dec/main.go b/03dec/main.go
new file mode 100644
index 0000000..1b1098b
--- /dev/null
+++ b/03dec/main.go
@@ -0,0 +1,25 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+)
+
+const (
+	W = iota
+	N
+	E
+	S
+)
+
+func main() {
+	n, err := strconv.Atoi(os.Args[1])
+	if err != nil {
+		os.Exit(1)
+	}
+	fmt.Println(n)
+
+	cur, x, y, dir, width, height := 1, 0, 0, W
+	// create cell and compute change direction, expand grid
+}