144-11

void Delete(Tree &T)
{
    if(T)
    {
        Delete(T->lchild);
        Delete(T->rchild);
        free(T);
    }
}

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

#define MaxSize 100

typedef struct node{
    int data;
    struct node *lchild,*rchild;
}TreeNode,*Tree;

typedef TreeNode* Elem;

typedef struct{
    Elem data[MaxSize];
    int front;
    int rear;
}Queue;

void InitQueue(Queue &Q)
{
    Q.front=Q.rear=0;
}

bool isEmpty(Queue Q)
{
    if(Q.front==Q.rear)
        return true;
    else
        return false;
}

bool isFull(Queue Q)
{
    if((Q.rear+1)%MaxSize==Q.front)
        return true;
    else
        return false;
}

bool EnQueue(Queue &Q,Elem p)
{
    if(isFull(Q))
        return false;
    Q.data[Q.rear]=p;
    Q.rear=(Q.rear+1)%MaxSize;
    return true;
}

bool DeQueue(Queue &Q,Elem &p)
{
    if(isEmpty(Q))
        return false;
    p=Q.data[Q.front];
    Q.front=(Q.front+1)%MaxSize;
    return true;
}

void CreateTree(Tree &T)
{
    int x;
    scanf("%d",&x);
    if(x==-1)
    {
        T=NULL;
        return;    
    }
    else
    {
        T=(TreeNode*)malloc(sizeof(TreeNode));
        T->data=x;
        printf("输入%d的左结点:",x);
        CreateTree(T->lchild);
        printf("输入%d的右结点:",x);
        CreateTree(T->rchild);
    }
}

void Delete(Tree &T)
{
    if(T)
    {
        Delete(T->lchild);
        Delete(T->rchild);
        free(T);
    }
}

void Select(Tree &T,int x)
{
    if(T->data==x)
    {
        Delete(T);
        return;
    }
    TreeNode *p=T;
    Queue Q;
    InitQueue(Q);
    EnQueue(Q,p);
    while(!isEmpty(Q))
    {
        DeQueue(Q,p);
        if(p->lchild)
        {
            if(p->lchild->data==x)
            {
                Delete(p->lchild);
                p->lchild=NULL;
            }
        }
        if(p->rchild)
        {
            if(p->rchild->data==x)
            {
                Delete(p->rchild);
                p->rchild=NULL;
            }
        }
    }
}

void PreOrder(Tree T)
{
    if(T==NULL)
        return;
    else
    {
        printf("%d  ",T->data);
        PreOrder(T->lchild);
        PreOrder(T->rchild);    
    }
    
}

int main()
{
    Tree T;
    CreateTree(T);
    PreOrder(T);
    printf("\n");
    Select(T,2);
    PreOrder(T);
    return 0;
}