Binary Tree Node - Insert, Delete

binaryTree.js

//     Root
//       |
//       |
// 11          12
// |           |   
// |           |
// 13  14      15  16
// |
// |
// 17 18


class TreeNode {
    constructor(value) {
      this.value = value;
      this.left = null;
      this.right = null;
    }
}

const rootNode = new TreeNode('Root');

rootNode.left = new TreeNode(11);
rootNode.right = new TreeNode(12);

rootNode.left.left = new TreeNode(13);
rootNode.left.right = new TreeNode(14);
rootNode.right.left = new TreeNode(15);
rootNode.right.right = new TreeNode(16);

rootNode.left.left.left = new TreeNode(17);
rootNode.left.left.right = new TreeNode(18);

function bfs(rootNode) {
    if(!rootNode) {
        return [];
    }

    let queue = [rootNode]
    let results = [];
    
    while(true) {
        const node = queue.shift();

        if(!node) {
            break;
        }

        results.push(node.value);

        if(node.left) {
            queue.push(node.left)
        }

        if(node.right) {
            queue.push(node.right)
        }
    }

    return results;
}

function insertNode(rootNode, value) {
    if(!rootNode) {
        return;
    }

    let queue = [rootNode]
    let results = [];
    
    while(true) {
        const node = queue.shift();

        if(!node) {
            break;
        }

        results.push(node.value);

        if(node.left) {
            queue.push(node.left)
        } else {
            node.left = new TreeNode(value)
            break;
        }

        if(node.right) {
            queue.push(node.right)
        } else {
            node.right = new TreeNode(value)
            break;
        }
    }    
}

function deleteNode(rootNode, value) {
    if(!rootNode) {
        return;
    }

    let queue = [rootNode]
    let results = [];
    
    while(true) {
        const node = queue.shift();

        if(!node) {
            break;
        }

        results.push(node.value);

        if(node.left) {
            if(node.left.value === value){
                node.left = null;
            } else{
                queue.push(node.left);
            }
        }

        if(node.right) {
            if(node.right.value === value){
                node.right = null;
            } else{
                queue.push(node.right);
            }
        }
    }    
}

bfs(rootNode);

insertNode(rootNode, 20)

bfs(rootNode);

deleteNode(rootNode, 13)

bfs(rootNode);