参考资料：《数据结构与算法分析——C语言描述》4.3一节

#include<stdio.h>
#include<stdlib.h>
#define N 10

typedef struct BinTreeNode
{
    int data;
    struct BinTreeNode *left;
    struct BinTreeNode *right;
}BinTreeNode,*BinTree;

BinTree insert(BinTree T,int data);//二叉树节点的添加
void PrintTree(BinTree T,void (*p)(BinTree T));//打印操作
void PrintTreeNode(BinTree T);//打印一个节点
BinTree Delete(BinTree T,int data);//删除某个节点
BinTree FindMin(BinTree T);//查找最小节点
BinTree FindMax(BinTree T);//查找最大节点
int FindMaxSubMin(BinTree T);//最大节点与最小节点的差值

int main()
{
    int i=0,n=0;
    int data[N]= {10,23,11,98,111,87,34,11,154,4};
    BinTreeNode *root=NULL;
    BinTree p;
    for(i=0;i<N;i++)
    {
        root=insert(root,data[i]);
    }
    PrintTree(root,PrintTreeNode);

    n=FindMaxSubMin(root);
    printf("%d\n",n);

    p=FindMin(root);
    PrintTreeNode(p);

    p=FindMax(root);
    PrintTreeNode(p);

    printf("\n");
    root=Delete(root,154);
    printf("\n");
    PrintTree(root,PrintTreeNode);
    printf("\n");

    n=FindMaxSubMin(root);
    printf("%d\n",n);

    p=FindMin(root);
    PrintTreeNode(p);

    p=FindMax(root);
    PrintTreeNode(p);

    root=Delete(root,1154);
    
    free(root);
    free(p);
    return 0;
}

BinTree insert(BinTree T,int data)
{
    if(T==NULL)
    {
        T=malloc(sizeof(BinTreeNode));
        if(T==NULL)
            printf("Out of space!\n");
        else
        {
            T->data=data;
            T->left=NULL;
            T->right=NULL;
        }
    }
    else
    {
        if(data<T->data)
            T->left=insert(T->left,data);
        else
            T->right=insert(T->right,data);
    }
    return T;
}

void PrintTreeNode(BinTree T)
{
    printf("%d\t",T->data);
}

//中序遍历
void PrintTree(BinTree T,void (*p)(BinTree T))
{
   if(T!=NULL)
   {
       PrintTree(T->left,p);//打印左子树
       p(T);//打印节点
       PrintTree(T->right,p);//打印右子树
   }
}

BinTree Delete(BinTree T,int data)
{
    BinTree temp;
    if(T==NULL)
        printf("\n%d not found.\n",data);
    else
    {
        if(data<T->data)
            T->left=Delete(T->left,data);
        else
        {
            if(data>T->data)
                T->right=Delete(T->right,data);
            else
            {
                if( T->left &&  T->right)//two children
                {
                    temp=FindMin(T->right);
                    T->data=temp->data;
                    T->right=Delete(T->right,T->data);
                }
                else//one or zero child
                {
                    temp=T;
                    if(T->left==NULL)
                        T=T->right;
                    else
                    {
                        if(T->right==NULL)
                            T=T->left;
                    }
                    free(temp);
                }
            }
        }
    }
    return T;
}

BinTree FindMin(BinTree T)
{
    if(T==NULL)
        return NULL;
    else
        if(T->left==NULL)
            return T;
        else return FindMin(T->left);
}

BinTree FindMax(BinTree T)
{
    if(T==NULL)
        return NULL;
    else
        if(T->right==NULL)
            return T;
        else return FindMax(T->right);
}

int FindMaxSubMin(BinTree T)
{
    int Max,Min;
    BinTree p;
    p=T;
    if(T==NULL)
        return 0;
    while(T->left!=NULL)
        T=T->left;
    Min=T->data;
    while(p->right)
        p=p->right;
    Max=p->data;
    return (Max-Min);
}