如何从2文件中读取interger元素到AVL树并找到公共元素？

Question

请帮助我进行此练习：

读取包含A和B卷的两个文件（每个文件包含可以重叠的整数，需要删除重复的数字），将A设置为大于B。删除重复的数字。在每组中重新打印文件A_out.txt，B_out.txt。找到并打印出这两个集合的共同元素。

#include<stdio.h>
#include<stdlib.h>
typedef struct node
{
     int data;
     struct node *left,*right;
     int ht;
 }node;
    node *Search(node *,int);
    node *insert(node *,int);
    node *Delete(node *,int);
    void preorder(node *);
    void inorder(node *);
    int height( node *);
    node *rotateright(node *);
    node *rotateleft(node *);
    node *RR(node *);
    node *LL(node *);
    node *LR(node *);
    node *RL(node *);
    int BF(node *);

    int main()
    {
        node *root=NULL;
        int x,n,i,op;

        do
        {
            printf("\n1)Create:");
            printf("\n2)Insert:");
            printf("\n3)Delete:");
            printf("\n4)Print:");
              printf("\n5)Search:");
            printf("\n6)Quit:");
            printf("\n\nEnter Your Choice:");
            scanf("%d",&op);

            switch(op)
            {
                case 1: printf("\nEnter no. of elements:");
                        scanf("%d",&n);
                        printf("\nEnter tree data:");
                        root=NULL;
                        for(i=0;i<n;i++)
                        {
                            scanf("%d",&x);
                            root=insert(root,x);
                        }
                        break;

                case 2: printf("\nEnter a data:");
                        scanf("%d",&x);
                        root=insert(root,x);
                        break;

                case 3: printf("\nEnter a data:");
                        scanf("%d",&x);
                        root=Delete(root,x);
                        break;

                case 4: printf("\nPreorder sequence:\n");
                        preorder(root);
                        printf("\n\nInorder sequence:\n");
                        inorder(root);
                        printf("\n");
                        break; 
                    case 5: printf("\nSearch Data:\n");
                        printf("\nEnter a data:");
                        scanf("%d",&x);
                              if(NULL==Search(root, x)) printf("%d is not EXIST!\n",x);
                              else printf("%d is EXIST!\n",x);      
                        break;           
            }
        }while(op!=6);

        return 0;
    }

    node * insert(node *T,int x)
    {
        if(T==NULL)
        {
            T=(node*)malloc(sizeof(node));
            T->data=x;
            T->left=NULL;
            T->right=NULL;
        }
        else
            if(x > T->data)        // insert in right subtree
            {
                T->right=insert(T->right,x);
                if(BF(T)==-2)
                    if(x>T->right->data)
                        T=RR(T);
                    else
                        T=RL(T);
            }
            else
                if(x<T->data)
                {
                    T->left=insert(T->left,x);
                    if(BF(T)==2)
                        if(x < T->left->data)
                            T=LL(T);
                        else
                            T=LR(T);
                }

            T->ht=height(T);

            return(T);
    }

    node *  Search(node *T,int x)
    {
       if(T==NULL) return NULL;
        if(x == T->data) return T;  
        else if(x > T->data) return Search(T->right, x);
        else return Search(T->left, x);
    }

    node * Delete(node *T,int x)
    {
        node *p;

        if(T==NULL)
        {
            return NULL;
        }
        else
            if(x > T->data)        // insert in right subtree
            {
                T->right=Delete(T->right,x);
                if(BF(T)==2)
                    if(BF(T->left)>=0)
                        T=LL(T);
                    else
                        T=LR(T);
            }
            else
                if(x<T->data)
                {
                    T->left=Delete(T->left,x);
                    if(BF(T)==-2)    //Rebalance during windup
                        if(BF(T->right)<=0)
                            T=RR(T);
                        else
                            T=RL(T);
                }
                else
                {
                    //data to be deleted is found
                    if(T->right!=NULL)
                    {    //delete its inorder succesor
                        p=T->right;

                        while(p->left!= NULL)
                            p=p->left;

                        T->data=p->data;
                        T->right=Delete(T->right,p->data);

                        if(BF(T)==2)//Rebalance during windup
                            if(BF(T->left)>=0)
                                T=LL(T);
                            else
                                T=LR(T);\
                    }
                    else
                        return(T->left);
                }
        T->ht=height(T);
        return(T);
    }

    int height(node *T)
    {
        int lh,rh;
        if(T==NULL)
            return(0);

        if(T->left==NULL)
            lh=0;
        else
            lh=1+T->left->ht;

        if(T->right==NULL)
            rh=0;
        else
            rh=1+T->right->ht;

        if(lh>rh)
            return(lh);

        return(rh);
    }

    node * rotateright(node *x)
    {
        node *y;
        y=x->left;
        x->left=y->right;
        y->right=x;
        x->ht=height(x);
        y->ht=height(y);
        return(y);
    }

    node * rotateleft(node *x)
    {
        node *y;
        y=x->right;
        x->right=y->left;
        y->left=x;
        x->ht=height(x);
        y->ht=height(y);

        return(y);
    }

    node * RR(node *T)
    {
        T=rotateleft(T);
        return(T);
    }

    node * LL(node *T)
    {
        T=rotateright(T);
        return(T);
    }

    node * LR(node *T)
    {
        T->left=rotateleft(T->left);
        T=rotateright(T);

        return(T);
    }

    node * RL(node *T)
    {
        T->right=rotateright(T->right);
        T=rotateleft(T);
        return(T);
    }

    int BF(node *T)
    {
        int lh,rh;
        if(T==NULL)
            return(0);

        if(T->left==NULL)
            lh=0;
        else
            lh=1+T->left->ht;

        if(T->right==NULL)
            rh=0;
        else
            rh=1+T->right->ht;

        return(lh-rh);
    }

    void preorder(node *T)
    {
        if(T!=NULL)
        {
            printf("%d(Bf=%d)",T->data,BF(T));
            preorder(T->left);
            preorder(T->right);
        }
    }

    void inorder(node *T)
    {
        if(T!=NULL)
        {
            inorder(T->left);
            printf("%d(Bf=%d)",T->data,BF(T));
            inorder(T->right);
        }
    }