[Java] 89. Binary Search Tree

package algo.bst.ch01;

class Node {
    int key;
    Node left;
    Node right;

    public Node(int key) {
        this.key = key;
    }
}

// BST -> 균형이 맞지 않는 트리
// B-tree -> 균형이 맞는 트리, 한 노드 당 3개, 노드의 차수가 2개면 자식 3개, 노드의 차수가 3개면 자식 4개
public class BinarySearchTree01 {
    public static void main(String[] args) {
        // 50 -> 30 -> 70 -> 20 -> 40 -> 60 -> 80 -> 10 -> 25 -> 35 -> 45
        Node root = new Node(50);

        root.left = new Node(30);
        root.right = new Node(70);

        root.left.left = new Node(20);
        root.left.right = new Node(40);
        root.right.left = new Node(60);
        root.right.right = new Node(80);

        root.left.left.left = new Node(10);
        root.left.left.right = new Node(25);
        root.left.right.left = new Node(35);
        root.left.right.right = new Node(45);

        // 출력 (전위)
        System.out.println(root.key);
        System.out.println(root.left.key + ",");
        System.out.println(root.left.left.key + ",");
        System.out.println(root.left.left.left.key + ",");
        System.out.println(root.left.left.right.key + ",");
        System.out.println(root.left.right.key + ",");
        System.out.println(root.left.right.left.key + ",");
        System.out.println(root.left.right.right.key + ",");
        System.out.println(root.right.key + ",");
        System.out.println(root.right.left.key + ",");
        System.out.println(root.right.right.key);

    }
}