https://www.mygreatlearning.com/blog/data-structures-using-java/ Array Linked List Stack  Queue Binary Tree Binary Search Tree Heap Hashing  Graph Array 固定長度 初始化: int a[] = {1,2,3};  int a[] = new int[]{1,2,3} int a[] = new int[3] int a[3] = new int[]{1,2,3} X int a[] = new int[3]{1,2,3} X