找出这个代码的错误并进行纠正：#include<stdio.h> #include<malloc.h> #include<conio.h> typedef struct tree { int data; struct tree*lchild; struct tree*rchild; }TREE; typedef struct stack { TREE*t; int flag; struct stack*link; }STACK; int push(STACK**top,TREE*tree) { STACK*p; p=(STACK*)malloc(sizeof(STACK)); p->t=tree; p->link=*top; *top=p; } int pop(STACK**top,TREE**tree) { STACK*p; if(*top==NULL) *tree=NULL; else { *tree=(*top)->t; p=*top; *top=(*top)->link; free(p); } } int SearchNode(TREE*tree, int key, TREE**pkpt, TREE**kpt) { *pkpt=NULL; *kpt=tree; while(*kpt!=NULL) { if((*kpt)->data==key) return 0; *pkpt=*kpt; if(key<(*kpt)->data) *kpt=(*kpt)->lchild; else *kpt=(*kpt)->rchild; } } int InsertNode(TREE**tree,int key) { TREE*p,*q,*r; SearchNode(*tree,key,&p,&q); if(q!=NULL) return 1; if((r=(TREE*)malloc(sizeof(TREE)))==NULL) return-1; r->data=key; r->lchild=r->rchild=NULL; if(p==NULL) *tree=r; else if(p->data>key) p->lchild=r; else p->rchild=r; return 0; } int DeleteNode(TREE**tree,int key) { TREE*p,*q,*r; SearchNode(*tree,key,&p,&q); if(q==NULL) return 1; if(p==NULL) if(q->lchild==NULL) *tree=q->rchild; else { *tree=q->lchild; r=q->lchild; while(r->rchild!=NULL) r=r->rchild; r->rchild=q->rchild; } else if(q->lchild==NULL) if(q==p->lchild) p->lchild=q->rchild; else p->rchild=q->rchild; else { r=q->lchild; r->rchild=q->rchild; if(q==p->lchild) p->lchild=q->lchild; else p->rchild=q->lchild; } free(q); return 0; }

这段代码存在以下错误：

1. push函数和pop函数的返回类型应该为void，因为它们没有返回值。
2. 在SearchNode函数中，如果key小于等于当前节点的值，应该将kpt指向左子节点，不然应该将kpt指向右子节点。
3. 在DeleteNode函数中，当q为要删除的节点时，如果p为NULL，应该将q的左子节点连接到q的右子节点的最左边节点，而不是最右边节点。

下面是修改后的代码：

#include <stdio.h>
#include <stdlib.h>
#include <conio.h>

typedef struct tree {
    int data;
    struct tree *lchild;
    struct tree *rchild;
} TREE;

typedef struct stack {
    TREE *t;
    int flag;
    struct stack *link;
} STACK;

void push(STACK **top, TREE *tree) {
    STACK *p;
    p = (STACK*)malloc(sizeof(STACK));
    p->t = tree;
    p->link = *top;
    *top = p;
}

void pop(STACK **top, TREE **tree) {
    STACK *p;
    if(*top == NULL) {
        *tree = NULL;
    }
    else {
        *tree = (*top)->t;
        p = *top;
        *top = (*top)->link;
        free(p);
    }
}

void SearchNode(TREE *tree, int key, TREE **pkpt, TREE **kpt) {
    *pkpt = NULL;
    *kpt = tree;
    while(*kpt != NULL) {
        if((*kpt)->data == key) {
            return;
        }
        *pkpt = *kpt;
        if(key <= (*kpt)->data) {
            *kpt = (*kpt)->lchild;
        }
        else {
            *kpt = (*kpt)->rchild;
        }
    }
}

int InsertNode(TREE **tree, int key) {
    TREE *p, *q, *r;
    SearchNode(*tree, key, &p, &q);
    if(q != NULL) {
        return 1;
    }
    if((r = (TREE*)malloc(sizeof(TREE))) == NULL) {
        return -1;
    }
    r->data = key;
    r->lchild = r->rchild = NULL;
    if(p == NULL) {
        *tree = r;
    }
    else if(p->data > key) {
        p->lchild = r;
    }
    else {
        p->rchild = r;
    }
    return 0;
}

int DeleteNode(TREE **tree, int key) {
    TREE *p, *q, *r;
    SearchNode(*tree, key, &p, &q);
    if(q == NULL) {
        return 1;
    }
    if(p == NULL) {
        if(q->lchild == NULL) {
            *tree = q->rchild;
        }
        else {
            *tree = q->lchild;
            r = q->lchild;
            while(r->rchild != NULL) {
                r = r->rchild;
            }
            r->rchild = q->rchild;
        }
    }
    else if(q->lchild == NULL) {
        if(q == p->lchild) {
            p->lchild = q->rchild;
        }
        else {
            p->rchild = q->rchild;
        }
    }
    else {
        r = q->lchild;
        r->rchild = q->rchild;
        if(q == p->lchild) {
            p->lchild = q->lchild;
        }
        else {
            p->rchild = q->lchild;
        }
    }
    free(q);
    return 0;
}