refactor: massive refactor to have only one binary to call

internal/2021/DayOne/code_test.go

@@ -0,0 +1,22 @@
+package dayone
+
+import "testing"
+
+var testInput = []int{199, 200, 208, 210, 200, 207, 240, 269, 260, 263}
+
+func TestPartOne(t *testing.T) {
+	expected := 7
+	got := PartOne(testInput)
+	if got != expected {
+		t.Errorf("PartOne() = %d, want %d", got, expected)
+	}
+}
+
+func TestPartTwo(t *testing.T) {
+	expected := 5
+	got := PartTwo(testInput)
+	if got != expected {
+		t.Errorf("PartTwo() = %d, want %d", got, expected)
+	}
+}
+