fix: the bug for the array binary tree from ts and js code (#936)

codes/javascript/chapter_tree/array_binary_tree.js

@@ -40,7 +40,7 @@ class ArrayBinaryTree {
 
     /* 获取索引为 i 节点的父节点的索引 */
     parent(i) {
-        return (i - 1) / 2;
+        return Math.floor((i - 1) / 2); // 向下取整
     }
 
     /* 层序遍历 */

codes/typescript/chapter_tree/array_binary_tree.ts

@@ -42,7 +42,7 @@ class ArrayBinaryTree {
 
     /* 获取索引为 i 节点的父节点的索引 */
     parent(i: number): number {
-        return (i - 1) / 2;
+        return Math.floor((i - 1) / 2); // 向下取整
     }
 
     /* 层序遍历 */
@@ -148,4 +148,4 @@ console.log('中序遍历为：' + res);
 res = abt.postOrder();
 console.log('后序遍历为：' + res);
 
-export {};
+export { };