没有平衡之前的，感觉好垃圾;

#include<iostream>
#include<cstdio>
using namespace std;
struct node{
    int l,r,date;
    int *newnode;
}tree[100001];
int d,bank=1;
void build(int pos,int date)
{
    if(tree[pos].date==0){tree[pos].date=date;return ;}
    else{
        if(date<=tree[pos].date){
            if(tree[pos].l==0)
             tree[pos].l=++bank;
        build(tree[pos].l,date);}
        else {
            if(tree[pos].r==0)
            tree[pos].r=++bank;
        build(tree[pos].r,date);}
       // cout<<bank<<" "<<endl;
    }
}
void mid(int x)
{
    if(x)
    {
        mid(tree[x].l);
        cout<<tree[x].date<<" ";
        mid(tree[x].r);
    }
}
int main()
{
    int n;
    scanf("%d",&n);
    for(int i=1;i<=n;i++)
    {
        scanf("%d",&d);
        build(1,d);
    }
    mid(1);
}