main.c

用C语言写的一个菜单程序

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "menu.h"


typedef struct pair {
    Node * parent;
    Node * child;
}Pair;

static Node * MakeNode(const Item * pm);
static void AddNode(Node * new_node ,Node * current_node, Node * root);
static bool CompareItem(Item * i1, Item * i2);


//初始化菜单
void InitializeMenu(Menu * pmenu){
    pmenu -> root;
    pmenu -> size = 0;
}
//确定菜单是否为空
bool MenuIsEmpty(Menu * pmenu){
    if(pmenu -> root == NULL)
        return true;
    else
        return false;
}

// 确定菜单是满
void MenuIsFull(const Menu * pmenu){
    if(pmenu -> size == MAXMENU)
        return true;
    else
        return false;
}

//返回菜单数
void MenuItemCount(const Menu * pmenu){
    return pmenu -> size;
}



//添加菜单
bool AddItem(const Item * pm,const Item * current_item,char * ch,Menu * pmenu){
    Node * new_node;
    if(MenuIsFull(pmenu)){
        fprintf(stderr,"Menu is full\n");
        return false;
    }
    //查找是否有重复菜单
    if(SeekItem(pm,pmenu).child != NULL){
        fprintf(stderr,"Attemped to add duplicate item\n");
        return false;
    }
    //创建新的节点
    new_node = MakeNode(pm);
    if(new_node == NULL){
        fprintf(stderr,"Couldn't create node\n");
        return false;
    }
    //菜单数加一
    pmenu -> size++;
    // 添加新节点到菜单
    if(pmenu -> root == NULL)
        pmenu -> root = new_node;
    else
        AddNode(new_node,current_item,ch,pmenu -> root,);
    return true;
}


//在菜单中查找用户指定的节点 ， 如果找到返回找到的节点， 否则返回NULL
//递归的方法实现，不建议使用
static void FindNode(Item * current_item , Node * root,Pair * pair){

    if(CompareItem(current_item  ,&root -> item)){
        //pair -> parent = & root;
        pair -> child = root;

    }else {
        if(root -> y != NULL)
            FindNode(current_item , root -> y,pair);

        if(root -> x != NULL)
            FindNode(current_item , root -> x,pair);
    }
}



//创建新节点
static Node * MakeNode(const Item * pm){
    Node * new_node;
    new_node = (Node *)malloc(sizeof(Node));
    if(new_node != NULL){
        //实现的代码涉及到数据类型，不好的代码
        strcpy(new_node -> item.name , pm -> name);
        new_node -> x = NULL;
        new_node -> y = NULL;
    }
    return new_node;
}

//在菜单中添加节点
static void AddNode(Node * new_node ,Node * current_node, char * ch ,Node * root){
    Pair look;
    look.parent = NULL;
    look.child = NULL;

    FindNode(&current_node -> item , root , & look)

    if(look.child != NULL)
        if(ch == 'Y'){
            while(look.child -> y != NULL)
                look.child = look.child -> y;
            look.child -> y = new_node ;
        }
        if(ch == 'X'){
            while(look.child -> x != NULL)
                look.child = look.child -> x;
            look.child -> y = new_node ;
        }
}



//节点的项目是否相等
static bool CompareItem(Item * i1, Item * i2){
    if(strcmp( i1 -> name ,i2 -> name ) == 0)
        return true;
    else
        return false;
}