fix: the rust variable should have a snake case name (#811)

codes/rust/chapter_divide_and_conquer/build_tree.rs

@@ -10,17 +10,17 @@ include!("../include/include.rs");
 use tree_node::TreeNode;
 
 /* 构建二叉树：分治 */
-fn dfs(preorder: &[i32], inorderMap: &HashMap<i32, i32>, i: i32, l: i32, r: i32) -> Option<Rc<RefCell<TreeNode>>> {
+fn dfs(preorder: &[i32], inorder_map: &HashMap<i32, i32>, i: i32, l: i32, r: i32) -> Option<Rc<RefCell<TreeNode>>> {
     // 子树区间为空时终止
     if r - l < 0 { return None; }
     // 初始化根节点
     let root = TreeNode::new(preorder[i as usize]);
     // 查询 m ，从而划分左右子树
-    let m = inorderMap.get(&preorder[i as usize]).unwrap();
+    let m = inorder_map.get(&preorder[i as usize]).unwrap();
     // 子问题：构建左子树
-    root.borrow_mut().left = dfs(preorder, inorderMap, i + 1, l, m - 1);
+    root.borrow_mut().left = dfs(preorder, inorder_map, i + 1, l, m - 1);
     // 子问题：构建右子树
-    root.borrow_mut().right = dfs(preorder, inorderMap, i + 1 + m - l, m + 1, r);
+    root.borrow_mut().right = dfs(preorder, inorder_map, i + 1 + m - l, m + 1, r);
     // 返回根节点
     Some(root)
 }
@@ -28,11 +28,11 @@ fn dfs(preorder: &[i32], inorderMap: &HashMap<i32, i32>, i: i32, l: i32, r: i32)
 /* 构建二叉树 */
 fn build_tree(preorder: &[i32], inorder: &[i32]) -> Option<Rc<RefCell<TreeNode>>> {
     // 初始化哈希表，存储 inorder 元素到索引的映射
-    let mut inorderMap: HashMap<i32, i32> = HashMap::new();
+    let mut inorder_map: HashMap<i32, i32> = HashMap::new();
     for i in 0..inorder.len() {
-        inorderMap.insert(inorder[i], i as i32);
+        inorder_map.insert(inorder[i], i as i32);
     }
-    let root = dfs(preorder, &inorderMap, 0, 0, inorder.len() as i32 - 1);
+    let root = dfs(preorder, &inorder_map, 0, 0, inorder.len() as i32 - 1);
     root
 }