diff --git a/contrib/ds-algorithms/index.md b/contrib/ds-algorithms/index.md
index dda6713..f6249d1 100644
--- a/contrib/ds-algorithms/index.md
+++ b/contrib/ds-algorithms/index.md
@@ -16,8 +16,7 @@
 - [Two Pointer Technique](two-pointer-technique.md)
 - [Hashing through Linear Probing](hashing-linear-probing.md)
 - [Hashing through Chaining](hashing-chaining.md)
-- [Binary Tree](binary_tree.md)
+- [Binary Tree](binary-tree.md)
 - [AVL Trees](avl-trees.md)
 - [Splay Trees](splay-trees.md)
-- [Splay Trees](splay-trees.md)
 - [Dijkstra's Algorithm](dijkstra.md)