經過對實驗目的及要求的分析，本實驗分為三個部分，分別為建立二叉樹、實現二叉樹的先序、中序、後序的遞迴演算法及二叉樹的中序的非遞迴演算法。

#include<cstdio>
#include<algorithm>
#include<queue>
using namespace std;
const int maxnode = 100000;

struct ArrayTree
{
    int node[maxnode];
    int num;
    void create()
    {
        int n; scanf("%d",&n);
        num = n;
        for(int i = 1 ; i <= n ; ++ i)
        {
            scanf("%d",node+i);
        }
    }
    void print()
    {
        for(int i = 1 ; i <=  num ; ++ i)
        {
            printf(" %d",node[i]);
        }
        printf("\n");
    }
};

struct node
{
    struct node* left;
    struct node* right;
    int value;
};

struct BiTree
{
    node* root;

    node* getnode()
    {
        node *child = (node*)malloc(sizeof(node));
        scanf("%d",&child->value);
        child->left = NULL; child->right = NULL;
        return child;
    }

    void create()
    {
        int n; scanf("%d",&n);
        queue<node*> q;
        root = (node*)malloc(sizeof(node));
        scanf("%d",&root->value);
        q.push(root);
        int i = 1;
        while(i<n)
        {
            node *rt = q.front(); q.pop();
            rt->left = getnode();
            q.push(rt->left); i++;
            if(i>=n) break;
            rt->right = getnode();
            q.push(rt->right); i++;
        }
    }
};

void pre_order(node* root)
{
    if(root==NULL) return;
    printf(" %d", root->value);
    if(root->left!=NULL)  pre_order(root->left);
    if(root->right!=NULL) pre_order(root->right);
}

void in_order(node* root)
{
    if(root->left!=NULL) in_order(root->left);
    if(root != NULL) printf(" %d",root->value);
    if(root->right!=NULL) in_order(root->right);
}

void post_order(node* root)
{
    if(root->left!=NULL) post_order(root->left);
    if(root->right!=NULL) post_order(root->right);
    if(root != NULL) printf(" %d",root->value);
}

int main()
{
    freopen("in","r",stdin);

    ArrayTree tmp;
    tmp.create();
    printf("\n順序儲存完全二叉樹:"); tmp.print();

    BiTree tree;
    tree.create();
    printf("\n前序遍歷二叉樹:"); pre_order(tree.root);
    printf("\n中序遍歷二叉樹:"); in_order(tree.root);
    printf("\n後序遍歷二叉樹");post_order(tree.root);

    return 0;
}