diff --git a/internal/data/2015/DayFour/input.txt b/internal/data/2015/DayFour/input.txt
new file mode 100644
index 0000000..0f84c61
--- /dev/null
+++ b/internal/data/2015/DayFour/input.txt
@@ -0,0 +1 @@
+iwrupvqb