diff --git a/internal/2025/DayTen/code_test.go b/internal/2025/DayTen/code_test.go
new file mode 100644
index 0000000..219a511
--- /dev/null
+++ b/internal/2025/DayTen/code_test.go
@@ -0,0 +1,17 @@
+package dayten
+
+import "testing"
+
+var testInput = []string{
+	"[.##.] (3) (1,3) (2) (2,3) (0,2) (0,1) {3,5,4,7}",
+	"[...#.] (0,2,3,4) (2,3) (0,4) (0,1,2) (1,2,3,4) {7,5,12,7,2}",
+	"[.###.#] (0,1,2,3,4) (0,3,4) (0,1,2,4,5) (1,2) {10,11,11,5,10,5}",
+}
+
+func TestPartOne(t *testing.T) {
+	expected := 7
+	got := PartOne(testInput)
+	if got != expected {
+		t.Errorf("PartOne() = %d, want %d", got, expected)
+	}
+}