diff --git a/.gitignore b/.gitignore
index c38fa4e..e5aa5b3 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,3 @@
 .idea
 *.iml
+target
\ No newline at end of file
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diff --git a/target/classes/edu/bit/carmanlee/datastruct/tree/TreeNode.class b/target/classes/edu/bit/carmanlee/datastruct/tree/TreeNode.class
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diff --git a/target/classes/edu/bit/carmanlee/datastruct/tree/TreeNodeInit.class b/target/classes/edu/bit/carmanlee/datastruct/tree/TreeNodeInit.class
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