Bug fixes and improvements (#1380)

* preorder, inorder, postorder -> pre-order, in-order, post-order

* Bug fixes

* Bug fixes

* Update what_is_dsa.md

* Sync zh and zh-hant versions

* Sync zh and zh-hant versions.

* Update performance_evaluation.md and time_complexity.md

* Add @khoaxuantu to the landing page.

* Sync zh and zh-hant versions

* Add @ khoaxuantu to the landing page of zh-hant and en versions.

zh-hant/codes/rust/include/vertex.rs

@@ -7,7 +7,7 @@
 /* 頂點型別 */
 #[derive(Copy, Clone, Hash, PartialEq, Eq)]
 pub struct Vertex {
-    pub val: i32
+    pub val: i32,
 }
 
 /* 輸入值串列 vals ，返回頂點串列 vets */
@@ -18,4 +18,4 @@ pub fn vals_to_vets(vals: Vec<i32>) -> Vec<Vertex> {
 /* 輸入頂點串列 vets ，返回值串列 vals */
 pub fn vets_to_vals(vets: Vec<Vertex>) -> Vec<i32> {
     vets.into_iter().map(|vet| vet.val).collect()
-}
+}