feat: finish BST print

app-ch9-13.js

@@ -9,6 +9,8 @@ class Node {
 class BinarySearchTree {
     constructor() {
         this.root = null;
+        this.path = '';
+        this.queue = [];
     }
 
     treeInsert(z) {
@@ -28,15 +30,68 @@ class BinarySearchTree {
             y.right = z;
         }
     }
+
+    preOrder(n){
+        if(n !== null){
+            this.path += n.key + ' ';
+            this.preOrder(n.left);
+            this.preOrder(n.right);
+        }
+    }
+
+    inOrder(n){
+        if(n !== null){
+            this.inOrder(n.left);
+            this.path += n.key + ' ';
+            this.inOrder(n.right);
+        }
+    }
+
+    postOrder(n){
+        if(n !== null){
+            this.postOrder(n.left);
+            this.postOrder(n.right);
+            this.path += n.key + ' ';
+        }
+    }
+
+    bftt(n){
+        if(n !== null){
+            this.queue.push(n);
+            for(let i=0; i<this.queue.length; i++){
+                const currentNode = this.queue[i];
+
+                if(currentNode){
+                    if(currentNode.left){
+                        this.queue.push(currentNode.left);
+                    }
+                    if(currentNode.right){
+                        this.queue.push(currentNode.right);
+                    }
+                }
+            }
+        }
+    }
 }
 
-const bst = new BinarySearchTree();
-bst.treeInsert(new Node(15));
-bst.treeInsert(new Node(6));
-bst.treeInsert(new Node(5));
-bst.treeInsert(new Node(1));
-bst.treeInsert(new Node(13));
-bst.treeInsert(new Node(-7));
-bst.treeInsert(new Node(3));
+const bst1 = new BinarySearchTree();
+const bst2 = new BinarySearchTree();
+const bst3 = new BinarySearchTree();
+const bst4 = new BinarySearchTree();
+const seeds = [15, 6, 5, 1, 13, -7, 3];
+
+seeds.forEach(seed =>{
+    bst1.treeInsert(new Node(seed));
+    bst2.treeInsert(new Node(seed));
+    bst3.treeInsert(new Node(seed));
+    bst4.treeInsert(new Node(seed));
+})
 
-console.log(bst);
+bst1.preOrder(bst1.root)
+bst2.inOrder(bst2.root)
+bst3.postOrder(bst3.root)
+bst4.bftt(bst4.root)
+console.log('PreOrder:', bst1.path)
+console.log('InOrder:', bst2.path)
+console.log('PostOrder:', bst3.path)
+console.log('BFTT:', bst4.queue.map(node => node.key).join(' '))