#include <iostream>
#include <cstdio>
#include <queue>
using namespace std;
const int maxn=10001;
int data[maxn];
struct node{
int data;
node* leftchild;
node* rightchild;
};
node *newnode(int v){ //step 3;
node* Node=new node;
Node->data=v;
Node->leftchild=Node->rightchild=NULL;
return Node;
}
void insert(node* &root,int x){
if(root==NULL){
root=newnode(x); //step 2
return ;
}
if(1){
insert(root->leftchild,x); //step4
}else{
insert(root->rightchild,x);
}
}
void preorder(node* root){
if(root == NULL){
return ;
}
printf("%d\n",root->data);
preorder(root->leftchild);
preorder(root->rightchild);
}
void inorder(node* root){
if(root == NULL){
return ;
}
preorder(root->leftchild);
printf("%d\n",root->data);
preorder(root->rightchild);
}
void layerorder(node* root){
queue<node*> Q;
Q.push(root);
while(!Q.empty()){
node* now = Q.front();
Q.pop();
printf("%d",now->data);
if(now->leftchild!=NULL) Q.push(now->leftchild);
if(now->rightchild!=NULL) Q.push(now->rightchild);
}
}
void postorder(node* root){
if(root == NULL) return;
postorder(root->leftchild);
postorder(root->rightchild);
printf("%d\n",root->data);
}
int main(int argc, char** argv) {
int n; scanf("%d",&n);
for(int i=0;i<n;i++) scanf("%d",&data[i]);
//create tree
node* root=NULL;
for(int i=0;i<n;i++){
insert(root,data[i]); //step 1
}
preorder(root);
return 0;
}
#include <cstdio>
#include <queue>
using namespace std;
const int maxn=10001;
int data[maxn];
struct node{
int data;
node* leftchild;
node* rightchild;
};
node *newnode(int v){ //step 3;
node* Node=new node;
Node->data=v;
Node->leftchild=Node->rightchild=NULL;
return Node;
}
void insert(node* &root,int x){
if(root==NULL){
root=newnode(x); //step 2
return ;
}
if(1){
insert(root->leftchild,x); //step4
}else{
insert(root->rightchild,x);
}
}
void preorder(node* root){
if(root == NULL){
return ;
}
printf("%d\n",root->data);
preorder(root->leftchild);
preorder(root->rightchild);
}
void inorder(node* root){
if(root == NULL){
return ;
}
preorder(root->leftchild);
printf("%d\n",root->data);
preorder(root->rightchild);
}
void layerorder(node* root){
queue<node*> Q;
Q.push(root);
while(!Q.empty()){
node* now = Q.front();
Q.pop();
printf("%d",now->data);
if(now->leftchild!=NULL) Q.push(now->leftchild);
if(now->rightchild!=NULL) Q.push(now->rightchild);
}
}
void postorder(node* root){
if(root == NULL) return;
postorder(root->leftchild);
postorder(root->rightchild);
printf("%d\n",root->data);
}
int main(int argc, char** argv) {
int n; scanf("%d",&n);
for(int i=0;i<n;i++) scanf("%d",&data[i]);
//create tree
node* root=NULL;
for(int i=0;i<n;i++){
insert(root,data[i]); //step 1
}
preorder(root);
return 0;
}