js递归，二叉树的操作

//递归算法n次幂function foo(n) { if (n == 1) { return 1; } else { return n * foo(n - 1); }}//console.log(foo(3));var nodes = { name: ‘root‘, childs: [ { name: ‘a1‘ }, { name: ‘a2‘ }, { name: ‘a3‘ }, { name: ‘b1‘ }, { name: ‘b2‘ }, { name: ‘b3‘, childs: [ { name: ‘bb1‘ }, { name: ‘bb2‘ }, { name: ‘bb3‘ } ] } ]}//递归树形节点function output(node) { console.log(node.name); if (node.childs && node.childs.length > 0) { node.childs.forEach(function (el, i) { //递归 output(el); }); }}//output(nodes);//二叉树var tree = { value: 100, left: { value: 80, left: { value: 70 }, right: { value: 90 } }, right: { value: 200, left: { value: 180 }, right: { value: 220 } }}//二叉树遍历（递归算法，容易导致运行栈溢出）function printTree(tree) { console.log(tree.value) if (tree.left) { printTree(tree.left); } if (tree.right) { printTree(tree.right); }}//printTree(tree);//二叉树的查找var count = 0;function findInTree(tree, v) { count++; if (v > tree.value && tree.right) { findInTree(tree.right, v) } else if (v < tree.value && tree.left) { findInTree(tree.left, v) } else if(v==tree.value){ console.log(‘存在该节点,节点值为:‘,tree.value); return 0; }else{ console.log(‘不存在该节点!‘); return -1; }}//findInTree(tree,70);//console.log(count);//二叉树的插入function insertTree(tree, v) { if (v > tree.value) { if (tree.right) {//如果有子节点继续遍历 insertTree(tree.right, v); } else { tree.right = { value: v }; } } else if (v < tree.value) { if (tree.left) {//如果有子节点继续遍历 insertTree(tree.left, v); } else { tree.left = { value: v }; } } else { console.log(‘树中已存在该节点‘); }}//insertTree(tree,505);//console.log(tree);//二叉树的生成(以一个数组中的任意元素为树的根节点)var data = [12, 23, 45, 123, 5, 89, 42, 32, 69, 11, 87, 25];//生成一个随机的索引var rindex = Math.floor(Math.random() * data.length);//随机获取data中的一个元素作为二叉树的根元素var prodTree = { value: data[rindex] };//使用根元素和数组为参数 创建索引function createTree(node, data) { data.forEach(function (v) { //将数组的每个元素插入二叉树中 insertTree(node,v); });}createTree(prodTree,data);//遍历生成的二叉树每个节点的值printTree(prodTree);