OJ傳送門

/*
 輸入一系列整數，建立二叉排序數，並進行前序，中序，後序遍歷
 */

#include <stdio.h>
#include <iostream>
using namespace std;
struct Node{
    Node *lchild;
    Node *rchild;
    int c;
}Tree[110];
int loc;

Node *creat(){
    Tree[loc].lchild=Tree[loc].rchild=NULL;
    return &Tree[loc++];
}

void postOrder(Node *T
 
){
    if (T->lchild!=NULL)
        postOrder(T->lchild);
    if (T->rchild!=NULL)
        postOrder(T->rchild);
    printf("%-3d",T->c);

}

void inOrder(Node *T){
    if (T->lchild!=NULL)
        postOrder(T->lchild);
    printf("%-3d",T->c);
    if (T->rchild!=NULL)
        inOrder(T
 
->rchild);

}

void preOrder(Node *T){
    printf("%-3d",T->c);
    if (T->lchild!=NULL)
        postOrder(T->lchild);
    if (T->rchild!=NULL)
        preOrder(T->rchild);

}


Node *Insert(Node *T,int x){
    if (T==NULL) {
        T=creat();
        T->c=x;
        return T;
    }
    else
 
 if(x<T->c)
        T->lchild=Insert(T->lchild, x);
    else if(x>T->c)
        T->rchild=Insert(T->rchild, x);
    return T;
}

int AVLTree(){
    int n;
    Node *T = NULL;
    while (scanf("%d",&n)!=EOF) {
        for (int i=0; i<n; i++) {
            int x;
            cin>>x;
            T=Insert(T,x);
        }
        preOrder(T);
        putchar('\n');
        inOrder(T);
        putchar('\n');
        postOrder(T);
        putchar('\n');
    }
    return 0;
}