2020-06-15二叉搜索树（BST）

function BinarySearchTree(){
  let Node=function(key){
    this.key=key
    this.left=null
    this.right=null
  }
  let root=null
  this.insert=function(key){
    let insertNode=function(node,newNode){
      if(newNode.keynode.key){
      return searchNode(node.right,key)
    }else{
      return true
    }
  }
  this.search=function(key){
    return searchNode(root,key)
  }
  let findMinNode=function(node){
    if(node){
      while(node&&node.left!==null){
        node=node.left
      }
      return node
    }
    return null
  }
  let removeNode=function(node,key){
    if(node===null){
      return null
    }
    if(keynode.key){
      node.right=removeNode(node.right,key)
      return node
    }else{
      //没有子节点
      if(node.left===null&&node.right===null){
        node=null
        return node
      }
      //只有一个子节点
      if(node.left===null){
        node=node.right
        return node
      }else if(node.right===null){
        node=node.left
        return node
      }
      //有两个子节点
      let aux=findMinNode(node.right)
      node.key=aux.key
      node.right=removeNode(node.right,aux.key)
      return node
    }
  }
  //删除某个节点
  this.remove=function(key){
    root=removeNode(root,key)
  }

  
}
let tree=new BinarySearchTree()
tree.insert(11)
tree.insert(7)
tree.insert(15)
tree.insert(5)
tree.insert(3)
tree.insert(9)
tree.insert(8)
tree.insert(10)
tree.insert(13)
tree.insert(12)
tree.insert(14)
tree.insert(20)
tree.insert(18)
tree.insert(25)
tree.insert(6)
function printNode(value){
  console.log(value)
}
//tree.inOrderTraverse(printNode)//3,5,6,7,8,9,10,11,12,13,14,15,18,20,25
//tree.preOrderTraverse(printNode)//11,7,5,3,6,9,8,10,15,13,12,14,20,18,25
// tree.postOrderTraverse(printNode)//3,6,5,8,10,9,7,12,14,13,18,25,20,15,11
// console.log(tree.min())//3
// console.log(tree.max())//25
// console.log(tree.search(1))//false
console.log(tree.search(8))//true
tree.remove(8)
console.log(tree.search(8))//false
tree.remove(15)
console.log(tree.search(15))//false