diff --git a/src/main/java/com/example/util/SubtractFunction.java b/src/main/java/com/example/util/SubtractFunction.java
new file mode 100644
index 0000000..029edd0
--- /dev/null
+++ b/src/main/java/com/example/util/SubtractFunction.java
@@ -0,0 +1 @@
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\ No newline at end of file