关于二叉树的前序遍历、中序遍历、删除元素、插入元素

#include<iostream> #include<cstdio> #include<queue> #include<cmath> #include<cstdlib> using namespace std; struct node { int data; struct node*left; struct node*right; }; node tree; struct node * create(int t) { node* tmp=new node; tmp->data=t; tmp->left=tmp->right=NULL; return tmp; } struct node * insert(struct node *root,int t) { if(root==NULL)root=create(t); if(root->data>t)root->left=insert(root->left,t); else if(root->data<t)root->right=insert(root->right,t); return root; } void preorder(struct node* root) { if(!root)return; printf("%d ",root->data); preorder(root->left); preorder(root->right); } void levelorder(struct node *root) { if(!root)return; queue<struct node*>q; q.push(root); while(!q.empty()) { struct node *tmp=q.front(); q.pop(); printf("%d ",tmp->data); if(tmp->left)q.push(tmp->left); if(tmp->right)q.push(tmp->right); } } int getheight(struct node* root) { if(!root)return 0; int h1=getheight(root->left); int h2=getheight(root->right); return 1+max(h1,h2); } struct node* Findmin(struct node* root) { if(!root)return NULL; struct node* tmp=root; while(tmp->left)tmp=tmp->left; return tmp; } struct node * Delete(struct node *root,int x) { if(!root)return NULL; if(x<root->data)root->left=Delete(root->left,x); else if(x>root->data)root->right=Delete(root->right,x); else { struct node *tmp=root; if(root->left&&root->right) { tmp=Findmin(root->right); root->data=tmp->data; root->right=Delete(root->right,root->data); } else { if(!root->left)root=root->right; else if(!root->right)root=root->left; else free(tmp); } } return root; } int main() { struct node* root=NULL; int n; cin>>n; for(int i=0;i<n;i++) { int t; cin>>t; root=insert(root,t); } preorder(root);//先序遍历 cout<<endl; levelorder(root); cout<<endl; cout<<getheight(root)<<endl; Delete(root,4); levelorder(root); cout<<endl; cout<<getheight(root)<<endl; return 0; }