diff --git a/07dec/input_test b/07dec/input_test
new file mode 100644
index 0000000..8a41324
--- /dev/null
+++ b/07dec/input_test
@@ -0,0 +1,13 @@
+pbga (66)
+xhth (57)
+ebii (61)
+havc (66)
+ktlj (57)
+fwft (72) -> ktlj, cntj, xhth
+qoyq (66)
+padx (45) -> pbga, havc, qoyq
+tknk (41) -> ugml, padx, fwft
+jptl (61)
+ugml (68) -> gyxo, ebii, jptl
+gyxo (61)
+cntj (57)
diff --git a/07dec/main.go b/07dec/main.go
new file mode 100644
index 0000000..9f995e3
--- /dev/null
+++ b/07dec/main.go
@@ -0,0 +1,49 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"strings"
+)
+
+func main() {
+	parents := make(map[string]bool)
+	children := make(map[string]bool)
+	sc := bufio.NewScanner(os.Stdin)
+	for sc.Scan() {
+		s := strings.Split(sc.Text(), " -> ")
+		parents[parseParent(s[0])] = true
+		if len(s) > 1 {
+			for _, c := range parseChildren(s[1]) {
+				children[c] = true
+			}
+		}
+	}
+	//fmt.Println(parents)
+	//fmt.Println(children)
+	fmt.Println(uniq(parents, children))
+}
+
+func parseParent(s string) string {
+	return strings.Split(s, " ")[0]
+}
+
+func parseChildren(s string) []string {
+	ret := []string{}
+	for _, c := range strings.Split(s, ", ") {
+		ret = append(ret, c)
+	}
+	return ret
+}
+
+func uniq(p map[string]bool, c map[string]bool) string {
+	for e := range c {
+		delete(p, e)
+	}
+	fmt.Println(len(p))
+	for e := range p {
+		return e
+	}
+	return "not found"
+}